18 results on '"Francesco Barsotti"'
Search Results
2. Lower limb deep vein thrombosis in COVID-19 patients admitted to intermediate care respiratory units
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Francesco Barsotti, Liliana Villari, Laura Carrozzi, Alessandro Celi, Roberta Pancani, Giulia Parri, Mario Malerba, Rigoletta Vincenti, Valentina Foci, and Filippo Patrucco
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Male ,Deep vein ,Comorbidity ,Respiratory failure ,030204 cardiovascular system & hematology ,law.invention ,0302 clinical medicine ,law ,Thrombophilia ,Prospective Studies ,Prospective cohort study ,Ultrasonography ,Aged, 80 and over ,DVT, deep vein thrombosis ,Incidence ,P/F, PaO2/FiO2 ,Incidence (epidemiology) ,Hematology ,Middle Aged ,Intensive care unit ,Thrombosis ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Female ,CUS, compression ultrasound ,Compression ultrasound, thrombosis ,COVID-19 ,Pneumonia ,medicine.symptom ,Intermediate Care Facilities ,Respiratory Insufficiency ,medicine.medical_specialty ,Hemorrhage ,Asymptomatic ,03 medical and health sciences ,Full Length Article ,Pressure ,medicine ,Humans ,thrombosis ,Aged ,SARS-CoV-2 ,business.industry ,Anticoagulants ,Compression ultrasound ,Thrombophlebitis ,medicine.disease ,LMWH, low molecular weight heparin ,Surgery ,CPAP, continuous positive airway pressure ,Pulmonary Embolism ,SD, standard deviation ,business ,Platelet Aggregation Inhibitors - Abstract
COVID-19 has been associated with an increased risk of thrombotic events; however, the reported incidence of deep vein thrombosis varies depending, at least in part, on the severity of the disease. Aim of this prospective, multicenter, observational study was to investigate the incidence of lower limb deep vein thrombosis as assessed by compression ultrasound in consecutive patients admitted to three pulmonary medicine wards designated to care for patients with COVID-19 related pneumonia, with or without respiratory failure but not requiring admission to an intensive care unit. Consecutive patients admitted between March 27 and May 6, 2020 were enrolled. Patients were excluded if they were less than 18-year-old or if compression ultrasound could not be performed for any reason. Patients were assessed at admission (t0) and after 7 days (t1). Major and non-major clinically relevant bleedings were recorded. Sixty-eight patients were enrolled. Two were excluded due to anatomical abnormalities that prevented compression ultrasound; sixty patients were retested at (t1). All patients were started on antithrombotic prophylaxis, unless therapeutic anticoagulation was required. Deep vein thrombosis as assessed by compression ultrasound was observed in 2 patients (3%); one of them was later deemed to represent a previous episode. No new episodes were detected at t1. One major and 2 non-major clinically relevant bleedings were observed. In the setting of patients with COVID-related pneumonia not requiring admission to an intensive care unit, the incidence of deep vein thrombosis is low and our data support not screening asymptomatic patients., Highlights • COVID-19 is characterized by increased risk of thrombotic events. • Compression ultrasound is an easy and reliable method to detect deep vein thrombosis. • The incidence of deep vein thrombosis in our COVID-19 patients not in ICU is very low. • Screening for deep vein thrombosis in these patients is not warranted.
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- 2021
3. Evaluating lexical resources using SENSEVAL.
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Nicoletta Calzolari, Claudia Soria, Francesca Bertagna, and Francesco Barsotti
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- 2002
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4. Formation of substances with humic-like fluorescence properties, upon photoinduced oligomerization of typical phenolic compounds emitted by biomass burning
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Marcello Brigante, Davide Vione, Bin Jiang, Alexandre Albinet, Sasho Gligorovski, Majda Mekic, Claudio Minero, Francesco Barsotti, Dipartimento di Chimica [Torino], Università degli studi di Torino = University of Turin (UNITO), Institut National de l'Environnement Industriel et des Risques (INERIS), State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, Institut de Chimie de Clermont-Ferrand (ICCF), SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), and Università degli studi di Torino (UNITO)
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Atmospheric Science ,Acetosyringone ,010504 meteorology & atmospheric sciences ,Vanillin ,Photodissociation ,010501 environmental sciences ,Photochemistry ,Mass spectrometry ,complex mixtures ,01 natural sciences ,7. Clean energy ,Fluorescence ,chemistry.chemical_compound ,Aerosol Biomass burning HuLiS Photolysis Methoxyphenols ,chemistry ,13. Climate action ,Yield (chemistry) ,Vanillic acid ,[CHIM]Chemical Sciences ,Guaiacol ,0105 earth and related environmental sciences ,General Environmental Science - Abstract
International audience; The irradiation under simulated sunlight of some phenolic compounds typically emitted in ambient air by biomass burning, namely vanillin and acetosyringone, yielded intermediates with humic-like fluorescence properties that can be assimilated to humic-like substances (HULIS). Evidence was obtained by ultra-high-resolution mass spectrometry of the occurrence of oligomerization processes up to the formation of trimeric species. In contrast, the irradiation of other biomass-burning compounds such as vanillic acid, m-cresol and guaiacol did not yield either HULIS-type fluorescence or oligomers. We suggest that the photolysis of biomass-burning compounds is a potential HULIS source in the atmosphere, if the relevant substrates undergo photoinduced oligomerization reactions.
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- 2019
5. Phototransformation of the Herbicide Propanil in Paddy Field Water
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Silvia Berto, Aldo Ferrero, Marco Minella, Francesco Barsotti, Marco Milan, Davide Vione, Marcello Brigante, Luca Carena, Claudio Minero, Dipartimento di Chimica [Torino], Università degli studi di Torino (UNITO), Institut de Chimie de Clermont-Ferrand (ICCF), SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università di Torino, Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Grugliasco, and Università degli studi di Torino = University of Turin (UNITO)
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Photolysis ,Herbicides ,Chemistry ,Photodissociation ,Water ,General Chemistry ,Propanil ,010501 environmental sciences ,010402 general chemistry ,01 natural sciences ,6. Clean water ,0104 chemical sciences ,chemistry.chemical_compound ,Nitrate ,Environmental chemistry ,Yield (chemistry) ,Dissolved organic carbon ,[CHIM]Chemical Sciences ,Environmental Chemistry ,Paddy field ,Nitrite ,Photodegradation ,Water Pollutants, Chemical ,0105 earth and related environmental sciences - Abstract
International audience; When irradiated in paddy-field water, propanil (PRP) undergoes photodegradation by direct photolysis, by reactions with •OH and CO3•–, and possibly also with the triplet states of chromophoric dissolved organic matter. Irradiation also inhibits the nonphotochemical (probably biological) degradation of PRP. The dark- and light-induced pathways can be easily distinguished because 3,4-dichloroaniline (34DCA, a transformation intermediate of considerable environmental concern) is produced with almost 100% yield in the dark but not at all through photochemical pathways. This issue allows an easy assessment of the dark process(es) under irradiation. In the natural environment, we expect PRP photodegradation to be important only in the presence of elevated nitrate and/or nitrite levels, e.g., [NO3–] approaching 1 mmol L–1 (corresponding to approximately 60 mg L–1). Under these circumstances, •OH and CO3•– would play a major role in PRP phototransformation. Because flooded paddy fields are efficient denitrification bioreactors that can achieve decontamination of nitrate-rich water used for irrigation, irrigation with such water would both enhance PRP photodegradation and divert PRP dissipation processes away from the production of 34DCA, at least in the daylight hours.
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- 2017
6. Computational assessment of the fluorescence emission of phenol oligomers: A possible insight into the fluorescence properties of humic-like substances (HULIS)
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Giovanni Ghigo, Davide Vione, and Francesco Barsotti
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010504 meteorology & atmospheric sciences ,General Chemical Engineering ,Radical ,General Physics and Astronomy ,Aromaticity ,General Chemistry ,010501 environmental sciences ,Dihedral angle ,Photochemistry ,01 natural sciences ,Oligomer ,Fluorescence ,chemistry.chemical_compound ,chemistry ,Phenol ,Density functional theory ,Conformational isomerism ,0105 earth and related environmental sciences - Abstract
Compounds with fluorescence in the humic-like substances (HULIS) region are known to be formed under conditions where the oxidation (which could lead to the oligomerization) of phenolic compounds is operational, because of the formation of phenoxy radicals. However, there was no evidence to date that such fluorescence emission was really due to phenol oligomers. In this work, the fluorescence of phenol and some of its oligomers was studied by computational methods and it was compared with experimental data, when allowed by the availability of commercial standards. The oligomer fluorescence depends on the contribution of different stable conformers, which differ from one another for the dihedral angles between the aromatic rings. Differences in the dihedral angles are also observed between the ground states and the corresponding excited singlet states. The predicted wavelengths of fluorescence emission increase with increasing the number of aromatic rings, up to a plateau at around 450 nm. Compounds with more than three-four aromatic rings are not expected to show emission in a different range, because the transitions causing fluorescence involve only three consecutive rings. These results support the hypothesis that oligomers account for the fluorescence emission in the HULIS region, which has been observed under the photochemical and photosensitized transformation of phenolic compounds.
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- 2016
7. NUtraceutical TReatment for hYpercholesterolemia in HIV-infected patients: The NU-TRY(HIV) randomized cross-over trial
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Massimo Raffaele Mannarino, Amirhossein Sahebkar, Franco Baldelli, Andrea Spinozzi, Elisabetta Schiaroli, Francesco Barsotti, Francesco Bagaglia, Matteo Pirro, Daniela Francisci, and Vanessa Bianconi
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0301 basic medicine ,Male ,HIV Infections ,030204 cardiovascular system & hematology ,Arterial stiffness ,HIV ,LDL-C ,Nutraceutical ,PCSK9 ,hs-CRP ,Gastroenterology ,chemistry.chemical_compound ,0302 clinical medicine ,Prospective Studies ,Pulse wave velocity ,Hypertriglyceridemia ,Hypoalphalipoproteinemias ,education.field_of_study ,Cross-Over Studies ,medicine.diagnostic_test ,Smoking ,Middle Aged ,C-Reactive Protein ,Hypertension ,lipids (amino acids, peptides, and proteins) ,Female ,Proprotein Convertase 9 ,Cardiology and Cardiovascular Medicine ,Glomerular Filtration Rate ,Adult ,medicine.medical_specialty ,Population ,Hypercholesterolemia ,Pulse Wave Analysis ,03 medical and health sciences ,Vascular Stiffness ,Internal medicine ,medicine ,Humans ,Obesity ,education ,Inflammation ,Triglyceride ,business.industry ,Cholesterol, LDL ,Overweight ,medicine.disease ,Lipid Metabolism ,Crossover study ,030104 developmental biology ,chemistry ,Dietary Supplements ,Lipid profile ,business ,Lipoprotein - Abstract
Background and aims Despite hypercholesterolemia has been recognized to increase cardiovascular risk in human immunodeficiency virus (HIV)-infected patients, cholesterol-lowering therapy is underused in this population, due to fear of drug-drug interactions with antiretroviral therapy (ART). We investigated the effects of a nutraceutical combination (NC) on lipid profile, proprotein convertase subtilisin/kexin type 9 (PCSK9), subclinical inflammation and arterial stiffness in ART-treated HIV-infected patients. Methods This was a prospective randomized open-label trial with a cross-over design including 30 stable HIV-infected patients on ART with low-density lipoprotein cholesterol (LDL-C) >115 mg/dL, not taking lipid-lowering treatment. After a 3-week lipid stabilization period, the effects associated with 3 months of an oral NC containing red yeast rice and berberine vs. no active treatment (noNC) were assessed for plasma total cholesterol (TC), LDL-C, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), lipoprotein(a), PCSK9, high-sensitivity C-reactive protein (hs-CRP) levels and aortic pulse wave velocity (aPWV). Results At baseline, significant correlations between PCSK9 levels, age (rho = −0.51, p=0.004), waist circumference (rho = 0.36, p=0.005) and CD4+ cell count (rho = −0.40, p=0.027) were observed. NC treatment effects corrected for noNC were significant for TC (−14%, p Conclusions The tested NC significantly reduced plasma cholesterol and PCSK9 levels, attenuated subclinical inflammation and improved arterial stiffness in stable HIV-infected patients on ART.
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- 2018
8. Simulation of photoreactive transients and of photochemical transformation of organic pollutants in sunlit boreal lakes across 14 degrees of latitude: A photochemical mapping of Sweden
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Francesco Barsotti, Claudio Minero, Tomas Landelius, Marco Minella, Lars J. Tranvik, Davide Vione, and Birgit Koehler
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Environmental Engineering ,010504 meteorology & atmospheric sciences ,Carbonates ,010501 environmental sciences ,Photochemistry ,01 natural sciences ,chemistry.chemical_compound ,Nitrate ,Dissolved organic carbon ,Organic Chemicals ,Photodegradation ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Water Science and Technology ,Civil and Structural Engineering ,Pollutant ,Sweden ,Photolysis ,Singlet Oxygen ,Singlet oxygen ,Hydroxyl Radical ,Ecological Modeling ,Eutrophication ,Photochemical Processes ,Pollution ,Colored dissolved organic matter ,Kinetics ,Lakes ,chemistry ,Boreal ,Models, Chemical ,Environmental chemistry ,Sunlight ,Carbonate ,Water Pollutants, Chemical - Abstract
Lake water constituents, such as chromophoric dissolved organic matter (CDOM) and nitrate, absorb sunlight which induces an array of photochemical reactions. Although these reactions are a substantial driver of pollutant degradation in lakes they are insufficiently understood, in particular on large scales. Here, we provide for the first time comprehensive photochemical maps covering a large geographic region. Using photochemical kinetics modeling for 1048 lakes across Sweden we simulated the steady-state concentrations of four photoreactive transient species, which are continuously produced and consumed in sunlit lake waters. We then simulated the transient-induced photochemical transformation of organic pollutants, to gain insight into the relevance of the different photoreaction pathways. We found that boreal lakes were often unfavorable environments for photoreactions mediated by hydroxyl radicals ( OH) and carbonate radical anions (CO3− ), while photoreactions mediated by CDOM triplet states (3CDOM*) and, to a lesser extent, singlet oxygen (1O2) were the most prevalent. These conditions promote the photodegradation of phenols, which are used as plastic, medical drug and herbicide precursors. When CDOM concentrations increase, as is currently commonly the case in boreal areas such as Sweden, 3CDOM* will also increase, promoting its importance in photochemical pathways even more.
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- 2017
9. Photochemical Formation of Nitrite and Nitrous Acid (HONO) upon Irradiation of Nitrophenols in Aqueous Solution and in Viscous Secondary Organic Aerosol Proxy
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Francesco Barsotti, Gilles Mailhot, Elisa De Laurentiis, Valter Maurino, Thorsten Bartels-Rausch, Markus Ammann, Marcello Brigante, Davide Vione, Claudio Minero, Dipartimento di Chimica [Torino], Università degli studi di Torino (UNITO), Laboratory of Environmental Chemistry, Paul Scherrer Institute, Villigen, Institut de Chimie de Clermont-Ferrand (ICCF), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Università degli studi di Torino = University of Turin (UNITO)
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Aerosols ,Nitrous acid ,Aqueous solution ,010504 meteorology & atmospheric sciences ,Chemistry ,Inorganic chemistry ,Nitrous Acid ,General Chemistry ,010501 environmental sciences ,Photochemical Processes ,Photochemistry ,01 natural sciences ,Aerosol ,Nitrophenols ,chemistry.chemical_compound ,13. Climate action ,Nitro ,Environmental Chemistry ,[CHIM]Chemical Sciences ,Irradiation ,Nitrite ,Nitrites ,0105 earth and related environmental sciences - Abstract
International audience; Irradiated nitrophenols can produce nitrite and nitrous acid (HONO) in bulk aqueous solutions and in viscous aqueous films, simulating the conditions of a high-solute-strength aqueous aerosol, with comparable quantum yields in solution and viscous films (10–5–10–4 in the case of 4-nitrophenol) and overall reaction yields up to 0.3 in solution. The process is particularly important for the para-nitrophenols, possibly because their less sterically hindered nitro groups can be released more easily as nitrite and HONO. The nitrophenols giving the highest photoproduction rates of nitrite and HONO (most notably, 4-nitrophenol and 2-methyl-4-nitrophenol) could significantly contribute to the occurrence of nitrite in aqueous phases in contact with the atmosphere. Interestingly, dew-water evaporation has shown potential to contribute to the gas-phase HONO levels during the morning, which accounts for the possible importance of the studied process.
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- 2017
10. The nature of the light absorption and emission transitions of 4-hydroxybenzophenone in different solvents. A combined computational and experimental study
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Silvia Berto, Giovanni Ghigo, Francesco Barsotti, and Davide Vione
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Excitation-emission fluorescence matrix, phototransformation, density functional theory, Kasha's rule ,Aqueous solution ,phototransformation ,Chemistry ,Analytical chemistry ,Kasha's rule ,010501 environmental sciences ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Fluorescence ,Excitation-emission fluorescence matrix ,0104 chemical sciences ,Excited state ,Singlet state ,Physical and Theoretical Chemistry ,Ground state ,Absorption (electromagnetic radiation) ,density functional theory ,Excitation ,0105 earth and related environmental sciences - Abstract
The photophysics and photochemistry of 4-hydroxybenzophenone (4HOBP) are interesting because they can give some insight into the behavior of humic material. Here we show that 4HOBP has a number of fluorescence peaks: (i) an intense one at excitation/emission wavelengths Ex/Em ∼ 200–230/280–370 nm, likely due to an excitation transition from S0 to S5 or S6, followed by S2 → S0 in emission (Sn denotes the singlet states of 4HOBP); (ii) a minor peak at Ex/Em ∼ 270–300/320–360 nm (S0 → S2 in absorption and S2 → S0 in emission), and (iii) very interesting signals in the typical emission region of humic substances, most notably at Ex/Em ∼ 200–220/400–500 nm and Ex/Em ∼ 260–280/400–470 nm (in both cases the emission corresponded to an S1 → S0 transition). The peak (i) (Ex/Em ∼ 200–230/280–370 nm) is quite intense at low 4HOBP concentration values, but it undergoes an effective inner-filter phenomenon. Remarkably, 4HOBP shows fluorescence peaks that arise from S2 → S0 transitions and that do not follow Kasha's rule. Fluorescence is observed in aprotic or poorly protic solvents, and to a lesser extent in aqueous solution. The excited states of 4HOBP, and most notably 4HOBP-S1, are much stronger acids than 4HOBP-S0. Therefore, excited 4HOBP is quickly deprotonated to 4OBP−-S0 in ∼neutral solution, with a considerable loss of the fluorescence properties. Higher fluorescence intensity can be observed under acidic conditions, where excited-state deprotonation is less effective, and in basic solution where the dissociated 4OBP−-S0 form prevails as the ground state. The excited states of 4OBP− are formed directly upon radiation absorption, and being weak bases they do not undergo important acid–base equilibria. Therefore, they can undergo radiational deactivation to produce significant fluorescence emission.
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- 2017
11. Considerable Fenton and photo-Fenton reactivity of passivated zero-valent iron
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Valter Maurino, Marco Minella, Khalil Hanna, Elisabetta Sappa, Francesco Barsotti, Davide Vione, Claudio Minero, Università degli studi di Torino (UNITO), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Torino = University of Turin (UNITO), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
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Nitration ,Passivation ,Reducing agent ,General Chemical Engineering ,Iron ,Inorganic chemistry ,Oxide ,02 engineering and technology ,Wastewater treatment ,010501 environmental sciences ,Iron compounds ,01 natural sciences ,Chemicals removal (water treatment) ,chemistry.chemical_compound ,Surface reactivity ,Permeable reactive barriers ,Oxidizing agent ,Oxidation ,[CHIM]Chemical Sciences ,Typical properties ,0105 earth and related environmental sciences ,Zerovalent iron ,Aqueous solution ,Chemistry ,Environmental remediation ,General Chemistry ,Human decontamination ,Degradation process ,021001 nanoscience & nanotechnology ,6. Clean water ,Ambient environment ,Solutions ,Zerovalent irons ,13. Climate action ,Leaching ,Leaching (metallurgy) ,0210 nano-technology ,Anoxic conditions ,Impurities - Abstract
International audience; The vulnerability of Zero-Valent Iron (ZVI) to passivation, which significantly decreases its surface reactivity, limits its use as a reducing agent in environmental remediation applications (e.g., permeable reactive barriers). Passivation of ZVI occurs rapidly in ambient environments due to the presence of oxygen and water, as well as during the reduction of contaminants (e.g. chlorinated and nitrated organic compounds) even in anoxic conditions. Passivated zero-valent iron (pZVI) particles are typically covered by an iron (hydr)oxide layer that entails a loss of the typical properties of this material, prevents the reductive activity to take place, and could made pZVI a waste to be disposed of. This work shows that pZVI has considerable Fenton (oxidizing) reactivity in the presence of H2O2 at acidic pH. The pZVI-Fenton process likely involves reaction between H2O2 and the pZVI surface or near-surface species, because the detected levels of leached Fe in the solution bulk were insufficient to account for the observed degradation processes. Still, leached Fe in the solution at pH 2 and 3 would be too concentrated for some possible applications (e.g. wastewater treatment, which would require an additional precipitation step to remove excess Fe). In such a case, operation at pH 4 would be preferred to maintain reasonable reactivity without measurable Fe leaching. The pZVI-Fenton process was inactive above pH 4, but reactivity could be extended up to pH 5 by UVA irradiation. Surprisingly, a pZVI sample that underwent an additional 78 day aging in aqueous solution exhibited a considerable ability to photochemically remove phenol despite a slower initial stage. These properties account for the possible use of a potential waste in decontamination reactions. © 2016 The Royal Society of Chemistry.
- Published
- 2016
12. A Methodology to Discriminate Between Hydroxyl Radical-induced Processes and Direct Charge-transfer Reactions in Heterogeneous Photocatalysis
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Francesco Barsotti, Davide Vione, Stefano Bertinetti, Emrah Özensoy, Claudio Minero, Valter Maurino, and Marco Minella
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Heterogeneous photocatalysis ,chemistry.chemical_compound ,chemistry ,Direct charge-transfer ,TiO2/Al2O3 binary oxides ,Photocatalysis ,Hydroxyl radical ,Charge (physics) ,Physical and Theoretical Chemistry ,Hydroxylation ,Photochemistry - Abstract
A method to assess the ability of a photocatalyst to induce reactions with free or trapped hydroxyl radicals versus direct charge-transfer processes is here proposed, based on the use of phenol and 2-hydroxybenzoic acid (salicylic acid) as test substrates. The rationale is that phenol degradation would be preferentially (although not exclusively) induced by hydroxyl radicals, while salicylic acid would mainly undergo direct charge-transfer oxidation. The use of t-butanol as selective OH scavenger is helpful to understand how much each substrate is a selective indicator of the intended reaction pathway in the presence of a given semiconductor oxide. Phenol and salicylic acid should be used at low concentration (e.g. 25 mol L1) to limit the occurrence of the backreactions, the importance of which can be highlighted by using higher initial concentration values (e.g. 1 mmol L1). The method was optimized with the well-studied photocatalysts Evonik P25 and Wackherr's Oxyde de titane standard, and it was then applied to study the behavior of two TiO2/Al2O3 binary oxide systems (where TiO2 occurs as a mixture of anatase and rutile). The latter photocatalysts were poorly efficient toward the degradation of phenol, but they performed better with salicylic acid. These findings, which are coherent with the results of t-butanol addition, suggest that the two binary oxide systems would induce charge-transfer rather than OH reactions.
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- 2016
13. A nutraceutical combination targeting dyslipidemia and subclinical inflammation in HIV patients on stable antiretroviral therapy
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Andrea Spinozzi, Massimo Raffaele Mannarino, Daniela Francisci, Matteo Pirro, Franco Baldelli, Francesco Barsotti, Francesco Bagaglia, Vanessa Bianconi, and Elisabetta Schiaroli
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medicine.medical_specialty ,Nutraceutical ,business.industry ,Internal medicine ,medicine ,Hiv patients ,Subclinical inflammation ,Cardiology and Cardiovascular Medicine ,business ,medicine.disease ,Antiretroviral therapy ,Dyslipidemia - Published
- 2018
14. Photochemical processes induced by the irradiation of 4-hydroxybenzophenone in different solvents
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Davide Vione, Marcello Brigante, Mohamed Sarakha, Francesco Barsotti, Valter Maurino, Claudio Minero, Università degli Studi di Torino, Dipartimento di Chimica, Torino, Institut de Chimie de Clermont-Ferrand (ICCF), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Torino, Centro Interdipartimentale NatRisk, Grugliasco, and Università degli studi di Torino = University of Turin (UNITO)
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LASER FLASH-PHOTOLYSIS ,PARA-HYDROXYBENZOPHENONE ,EXCITED SINGLET-STATE ,Chemistry ,Singlet oxygen ,MOUNTAIN LAKES ,AROMATIC-MOLECULES ,SUBSTITUTED BENZOPHENONES ,OPTICAL-PROPERTIES ,Photochemistry ,Solvent ,chemistry.chemical_compound ,Deprotonation ,Excited state ,DISSOLVED ORGANIC-MATTER ,[CHIM]Chemical Sciences ,MOLECULAR-OXYGEN ,HUMIC SUBSTANCES ,Singlet state ,Physical and Theoretical Chemistry ,Triplet state ,Acetonitrile ,Protic solvent - Abstract
The singlet and triplet excited states of 4-hydroxybenzophenone (4BPOH) undergo deprotonation in the presence of water to produce the anionic ground-state, causing fluorescence quenching and photoactivity inhibition. The same process does not take place in an aprotic solvent such as acetonitrile. In acetonitrile, 4BPOH is fluorescent (interestingly, one of its fluorescence peaks overlaps with peak C of humic substances), it yields singlet oxygen upon irradiation and induces the triplet-sensitised transformation of phenol (with a rate constant of (6.6 ± 0.3) × 107 M−1 s−1 (μ ± σ) between phenol itself and a triplet 4BPOH). The 4BPOH shows an intermediate behaviour in a partially protic solvent such as 2-propanol, where some deprotonation of the excited states is observed. In acetonitrile/2-propanol mixtures (at least up to 50% of 2-propanol) there is also some evidence of alcohol oxidation by the 4BPOH triplet state, while the experimental data are silent concerning such a possibility in pure 2-propanol. Considering that benzophenones are important components of chromophoric dissolved organic matter (CDOM) in surface waters, the present findings could have significance for the photoactivity of the hydrophilic surface layers vs. the hydrophobic cores of CDOM.
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- 2015
15. Evaluating lexical resources using S<scp>ENSEVAL</scp>
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Francesco Barsotti, Nicoletta Calzolari, Francesca Bertagna, and Claudia Soria
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Linguistics and Language ,Semantic annotation ,business.industry ,Computer science ,Context (language use) ,Sample (statistics) ,Lexicon ,computer.software_genre ,Object (computer science) ,Language and Linguistics ,Task (project management) ,Annotation ,Artificial Intelligence ,Artificial intelligence ,business ,computer ,Software ,Natural language processing - Abstract
The aim of our paper is twofold: to introduce some general reflections on the task of lexical semantic annotation and the adequacy of existing lexical-semantic reference resources, while giving an overall description of the Italian lexical sample task for the SENSEVAL-2 experiment. We suggest how the SENSEVAL exercise (and comparison between the two editions of the experiment) can be employed to evaluate the lexical reference resources used for annotation. We conclude with a few general remarks on the gap between the lexicon, a partially decontextualised object, and the corpus, where context plays a significant role.
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- 2002
16. UV–vis spectral modifications of water samples under irradiation: Lake vs. subterranean water
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Francesco Barsotti, Marco Isaia, Claudio Minero, Silvia Berto, Elisa De Laurentiis, Roberto Buscaino, Valter Maurino, Davide Vione, and Babita Sur
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Absorption spectroscopy ,Chemistry ,Photochemistry ,General Chemical Engineering ,Subterranean environments ,Analytical chemistry ,General Physics and Astronomy ,General Chemistry ,Humic and fulvic acids ,Phototransformation ,UV–vis spectrophotometry ,Fluorescence matrix ,Non-purgeable organic carbon ,Photobleaching ,Absorbance ,Colored dissolved organic matter ,Ultraviolet visible spectroscopy ,Environmental chemistry ,Epilimnion ,Dissolved organic carbon ,Exponential decay - Abstract
Water samples from subterranean systems (caves and abandoned mines) and from lake epilimnion were optically characterised and irradiated under simulated sunlight, to study the effects that sunlight exposure before sampling may have on the properties and photochemical behaviour of chromophoric dissolved organic matter (CDOM). Differently from lakes, absorption spectra of subterranean water samples showed variations from the typically observed, featureless exponential decay of absorbance vs. wavelength. Fluorescence spectra suggested that, compared to lake water and with a single exception, subterranean water had higher proportion of aquagenic/autochthonous CDOM ( e.g. proteinaceous material) compared to pedogenic/allochthonous one ( e.g. humic and fulvic substances). Irradiation of subterranean water produced very significant spectral changes, and finally yielded lakewater-like exponential absorption spectra. In contrast, irradiation of lake water produced photobleaching (decrease of the absorbance), but the shapes of absorption spectra underwent very limited variations. Tyrosine and humic acids were irradiated as proxies of the CDOM fractions identified by fluorescence. Irradiated tyrosine underwent a significant increase of the absorbance and finally yielded an exponential absorption spectrum, with close resemblance to the behaviour of a protein-rich and humic-poor sample of subterranean water. In contrast, irradiated humic acids underwent photobleaching in a similar way as lake water, but they retained their typical exponential spectrum. The present findings suggest that exposure of CDOM to sunlight may play a key role in shaping the exponential absorption spectra that are typically observed in surface waters.
- Published
- 2013
17. The syntactic-semantic treebank of Italian. An overview
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Simonetta, Montemagni, Francesco, Barsotti, Marco, Battista, Nicoletta, Calzolari, Ornella, Corazzari, Alessandro, Lenci, Vito, Pirrelli, Antonio, Zampolli, Francesca, Fanciulli, Maria, Massetani, Remo, Raffaelli, Roberto, Basili, Maria Teresa Pazienza, Dario, Saracino, Fabio, Zanzotto, Nadia, Mana, Fabio, Pianesi, and Delmonte, Rodolfo
- Subjects
linguistically interpreted corpora ,multi-layered linguistic annotation ,syntactic annotation ,semantic annotation ,annotation software - Published
- 2003
18. Building the Italian Syntactic-Semantic Treebank
- Author
-
Rodolfo Delmonte, Dario Saracino, Maria Teresa Pazienza, Antonio Zampolli, Francesca Fanciulli, Ornella Corazzari, Alessandro Lenci, Maria Massetani, Nadia Mana, Roberto Basili, Nicoletta Calzolari, Remo Raffaelli, Simonetta Montemagni, Fabio Massimo Zanzotto, Marco Battista, Fabio Pianesi, and Francesco Barsotti
- Subjects
Engineering ,Settore INF/01 - Informatica ,business.industry ,Speech recognition ,Treebank ,computer.software_genre ,Settore L-LIN/01 - Glottologia e Linguistica ,Resource (project management) ,Software ,Intelligent interface ,Artificial intelligence ,business ,Settore ING-INF/05 - Sistemi di Elaborazione delle Informazioni ,computer ,Natural language processing - Abstract
The paper reports on the design and construction of a multi-layered corpus of Italian, annotated at the syntactic and lexico-semantic levels, whose development is supported by dedicated software augmented with an intelligent interface. The issue of evaluating this type of resource is also addressed.
- Published
- 2003
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