Circular economy (CE) is now gaining attention in academia and industry as an emerging model for ... more Circular economy (CE) is now gaining attention in academia and industry as an emerging model for minimizing primary resource depletion, waste and greenhouse gas emissions. In the present work, we present a learning pathway, designed for high schools, useful to introduce some basic concepts of CE among youngsters by starting from a laboratory experience. The path was developed in the framework of the European project Raw Matters Ambassadors at Schools (RM@Schools), an innovative program to make science education attractive for youngsters which and to promote a wide dissemination action on raw material-related themes in Schools and Society. In this context, lab experiments to approach raw materials (RMs) considered critical by EU and the necessity of their recovery were set up for high school students. Phosphate rock (P) is one of the critical RMs for EU, and it is primarily used in agriculture. After 2033 Iit is expected a huge decline in P extraction and consequently, a dramatic dec...
Spectroscopic and pulse radiolysis studies of the antioxidant properties of (+)catechin: Metal ch... more Spectroscopic and pulse radiolysis studies of the antioxidant properties of (+)catechin: Metal chelation and oxidizing radical scavenging
Cimetidine (cim) is one of the most potent histamine H2‐receptor antagonists for inhibiting exces... more Cimetidine (cim) is one of the most potent histamine H2‐receptor antagonists for inhibiting excessive acid secretion caused by histamine; it has been hypothesized that the therapeutic effects can be related to its interactions with metal ions. Raman spectra of the solid cim with Co(II), Cu(II), Ni(II) and Zn(II) metal complexes show that they can adopt two different structures: one is octahedral and the other, with Zn(II), is probably tetrahedral. The octahedral structure appears to be distorted both by the different metal ions as well as by the different anion present. The study was extended to very dilute solutions (ppm range) by using the surface‐enhanced Raman scattering (SERS) technique, mimicking the physiological concentrations of cim and its metal complexes. SERS spectra suggest that, upon the binding of cim to silver colloids, the formation of stable 1:2 cim–metal complexes is excluded, the formation of 1:1 adduct appearing more probable; in this product the metal reaches i...
The adsorption effect of proteins on liposomal bilayer membranes plays a noticeable role in the u... more The adsorption effect of proteins on liposomal bilayer membranes plays a noticeable role in the use of liposomes as drug delivery systems. To explain th\uecs behaviour and correlate it with the protein properties, the thermal behaviour the hydrated multilamellar vesicles (liposomes) of dimyristoylphosphatidylcholine (DMPC) in the presence of increasing amounts of both lysozyme (Lyso) and bovine serum albumine (BSA) at pH = 7.0 was studied by means of Differential Scanning Calorimetry (DSC) technique. Liposomes were prepared mixing DMPC with the protein/water mixtures to a final lipid concentration of about 20% w/w and then incubated 1h at 37\ub0C. DSC scans were performed by a Mettler-Toledo DSC 821C calorimeter at a heating rate of 2.0\ub0C/min. In the samples with the lower Lyso concentrations (up to 2% w/w), a small decrease of about 0.2\ub0C on the main transition temperature (Tm) was observed, whereas Tm increased from 23.3 up to 24.1\ub0C by further addition of the Lyso amount (up to 15%). Contemporaneously, a increase of about 25% on the AH of the transition was observed. The pretransition was affected in a greater extent by the protein presence. Indeed, Tpr, after a small decrease of about 0.5 \ub0C in the 2% Lyscontaining sample, increased from 12.8 to U.4\ub0C in the 15% Lyso-containing samples, with a contemporary 35% increase in the associated AH value. In the presence of BSA a smaller increase (from 23.3 to 23.6\ub0C) in the Tm values was observed, in addition to a contemporary increase of about 10% in the associated AH. On the contrary, at the same conditions, a greater Tpr increase (from 12.8 to 15.2'C) took place. The data suggest that the interaction BSA-liposome involve only the external surface of the bilayer, excluding thus any penetration into the liposomial hydrophobic core. On the contrary, in the presence of Lyso, a partial penetration into the bilayer cannot be excluded, as suggested from the low Tm and Tpr decrease observed in the lower Lyso-containing samples. In the presence of both considered protein the overall bilayer structure of DMPC liposomes is strengthened, suggesting a decrease in the membrane permeability
Poly(epsilon-caprolactone) (PCL), an aliphatic polyester, has received much attention because of ... more Poly(epsilon-caprolactone) (PCL), an aliphatic polyester, has received much attention because of its possible application as both a biocompatible and a biodegradable material. For biomedical purposes, PCL-based products can be used as drug delivery systems to the human body or tissue engineering scaffold material. In the latter case the three dimensional synthetic scaffolds, implanted at the tissue defect site, provide a frame-work for cells to attach, proliferate and form extra cellular matrix. To enhance bone regeneration process, hydroxyapatite (HA), the main component of the inorganic phase of bone, is generally added to the polymer material. Response of the organism to the implanted composite biomaterial depends on numerous factors, one of the most important is sterilisation. Different procedures can be utilised for sterilisation, among them high energy radiations present many benefits. In fact, because of excellent penetration characteristics of ionising radiations, radiation sterilisation eliminates problems associated with residual and ethylene oxide gas penetration, uniformity of sterilisation, etc. The doses for radiation sterilization for medical devices and health care products are established by procedures defined in standard ISO 11137. For tissue allografts, international tissue bank standard recommended 15 kGy* as a minimum dose for bacteria decontamination and 25 kGy as minimum dose for bacteria sterilization. These doses should be validated using procedures established by ISO 11137. Other international tissue banks recommended dose up to 35 kGy. However, high-energy radiation, in addition killing bacterial life, may also affect material properties and the interaction between the different phase of the material. This study was aimed at evaluating possible irradiation-induced effects on morphological and thermal properties of both inorganic and polymeric components of some PCL-HA composites. To this purpose PCL-HA samples with different PCL/HA ratios were exposed to gamma radiations. The sample irradiation was performed at 50 kGy, dose greater than the recommended sterilization dose range under N2 or air atmosphere. The samples were investigated by vibrational spectroscopy (IR and Raman spectroscopies) coupled to thermal analysis measurements (Differential Scanning Calorimetry and Thermogravimetry) which revealed to be highly sensible to structure variations
DOT (2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane) was a widely used chlorinated pesticide. It i... more DOT (2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane) was a widely used chlorinated pesticide. It is characterized by a high environmental persistence time and accumulation in the fat tissues of living organisms. Furthermore, like other lipophilic substances, it can interact with biomembranes inducing membrane structure modification which could play a role both in the transport to the target tissues as well in the development of the toxicity. To this purpose we studied by means of Differential Scanning Calorimetry (DSC) the hydrated multilamellar liposomes of both Dimyristoyl phosphatidylcholine (DMPC) and Dimyristoyl phosphatidyletanolamine (DMPE) in the presence of increasing amounts of DOT. Liposomes were prepared by mixing the appropriate amount of DMPC and DMPE in a NaCI 0.9 % w/w solution up to a final lipid concentration of about 20 % w/w. DSC scans were performed at a heating rate of 2.0\ub0C/min in the thermal ranges of 5-40\ub0C and 25-60\ub0C for DMPC and DMPE samples respectively. The results on DDT/DMPC liposomes show significant Tm decrease and half width increase. The changes, more evident at low DDT concentration (up to 5.0 % w/w) suggest that the hydrophobic core is strongly affected by the presence of DDT molecules, their deep penetration into the bilayer are only partially prevented by the potar interactions between th\ue8 C-CI;i group and the DMPC polar head. In the presence of a greater DMPC amount, the Tm stays unchanged and half width increase slowly suggesting that the DDT solubility into the hydrophobic lipidic bilayer is limited. On the contrary DDT/DMPE liposomes show the presence of a phase segregation that takes piace in the presence of very small amount of DDT. This findings suggest that the DDT molecules interact mainly with th\ue8 outer face of the bilayer and only secondly with the inner hydrophobic core as consequence of the setting up of strong polar interactions involving the more polar head group of DMPE head groups. Also in the high concentrated DDT/DMPE mixtures (DDT > 5.0 % w/w), the shape of the thermograms does not change, confirming the DDT limited solubility into the bilayer
Membrane lipids play an important role in maintaining the normal function and structure of biomem... more Membrane lipids play an important role in maintaining the normal function and structure of biomembranes in plant and animal cells. Studies with some herbicides indicate that these substances interfere with plant membrane functions. The s-triazine herbicides, such as N,N’-Bis (l-methylethyl)-6-methyl-thio-l,3,5-triazine-2,4-diamine (prometryn), are widely used in agriculture; previous investigations have supported the idea biomembranes may be the primary targets of their action.
Raman spectra of avidin, biotin and the avidin‐biotin complex were recorded. The percentages of s... more Raman spectra of avidin, biotin and the avidin‐biotin complex were recorded. The percentages of secondary structure of avidin and the avidin‐biotin complex were obtained from the Raman spectra. The vibrational results indicate that, as a consequence of the interaction of avidin with biotin, the β‐sheet conformation percentage decreases and the α‐helical conformation percentage increases. Moreover, the interaction of avidin with biotin is also able to change slightly the tertiary structure of the protein. In fact, as a consequence of the binding of biotin, the hydrophobicity of the environment of Trp increases slightly according to the intensity increase of the 1360 cm−1 component. The intesity of all bands attributable to Trp residues increases with biotin binding, indicating that Trp is directly involved in the interaction. These results are in agreement with the results of UV measurements which indicate a red shift of the avidin Trp absorption bands as a consequence of the binding to biotin.
Luteolin (LUT) is a polyphenolic compound, found in a variety of fruits, vegetables, and seeds, w... more Luteolin (LUT) is a polyphenolic compound, found in a variety of fruits, vegetables, and seeds, which has a variety of pharmacological properties. In the present contribution, binding of LUT to human serum albumin (HSA), the most abundant carrier protein in the blood, was investigated with the aim of describing the binding mode and parameters of the interaction. The application of circular dichroism, UV-Vis absorption, fluorescence, Raman and surface-enhanced Raman scattering spectroscopy combined with molecular modeling afforded a clear picture of the association mode of LUT to HSA. Specific interactions with protein amino acids were evidenced. LUT was found to be associated in subdomain IIA where an interaction with Trp-214 is established. Hydrophobic and electrostatic interactions are the major acting forces in the binding of LUT to HSA. The HSA conformations were slightly altered by the drug complexation with reduction of alpha-helix and increase of beta-turns structures, suggesting a partial protein unfolding. Also the configuration of at least two disulfide bridges were altered. Furthermore, the study of molecular modeling afforded the binding geometry.
The harmful effects of oxidative processes in living organisms can be reduced by the dietary inta... more The harmful effects of oxidative processes in living organisms can be reduced by the dietary intake of flavonoids, a class of phenolic compounds ubiquitous in plants and widely found in a number of fruits, vegetables and beverages. Many fruits and vegetables are treated by irradiation to solve preservation problems and a radical-induced degradation of nutrients, including polyphenols, may occur. The free radical chemistry of two abundant flavonoids in food, catechin and quercetin, have been investigated by using pulse radiolysis technique. The central role of the phenoxyl-type radical and the strong influence of the state of protonation of the compounds on the pathway of formation and decay of the corresponding oxidized radicals has been evidenced from the spectral properties and chemical reactivity of the radicals derived from the attack of several oxidizing species (⋅OH, N3⋅ SO4−⋅).
The proposed curative properties of Cu-based nonsteroidal anti-inflammatory drugs (NSAIDs) have l... more The proposed curative properties of Cu-based nonsteroidal anti-inflammatory drugs (NSAIDs) have led to the development of numerous Cu(II) complexes of NSAIDs with enhanced anti-inflammatory activity. Crystalline complexes, Cu(II)-NSAID (ibuprofen, naproxen, tolmetin, and diclofenac), with a carboxylic function have been studied by means of infrared and Raman spectroscopy. All NSAIDs bind the metal through the carboxylate group. On the basis of the comparison between the wavenumber of the COO(-) group vibrations and Delta nu (nu(asimm)COO(-) - nu(simm)COO(-)) between Na salts and Cu(II) complexes, conclusions on the probable structure of the complexes have been drawn. The spectroscopic data support the formation of dimeric [Cu(2)L(4)(H(2)O)(2)] complexes in which the COO(-) group behaves as a bridging bidentate ligand. The low wavenumber region of the Raman spectrum provided information on Cu-O and Cu-Cu bonds in the complexes. Thermogravimetric results gave further support to the vibrational data
Circular economy (CE) is now gaining attention in academia and industry as an emerging model for ... more Circular economy (CE) is now gaining attention in academia and industry as an emerging model for minimizing primary resource depletion, waste and greenhouse gas emissions. In the present work, we present a learning pathway, designed for high schools, useful to introduce some basic concepts of CE among youngsters by starting from a laboratory experience. The path was developed in the framework of the European project Raw Matters Ambassadors at Schools (RM@Schools), an innovative program to make science education attractive for youngsters which and to promote a wide dissemination action on raw material-related themes in Schools and Society. In this context, lab experiments to approach raw materials (RMs) considered critical by EU and the necessity of their recovery were set up for high school students. Phosphate rock (P) is one of the critical RMs for EU, and it is primarily used in agriculture. After 2033 Iit is expected a huge decline in P extraction and consequently, a dramatic dec...
Spectroscopic and pulse radiolysis studies of the antioxidant properties of (+)catechin: Metal ch... more Spectroscopic and pulse radiolysis studies of the antioxidant properties of (+)catechin: Metal chelation and oxidizing radical scavenging
Cimetidine (cim) is one of the most potent histamine H2‐receptor antagonists for inhibiting exces... more Cimetidine (cim) is one of the most potent histamine H2‐receptor antagonists for inhibiting excessive acid secretion caused by histamine; it has been hypothesized that the therapeutic effects can be related to its interactions with metal ions. Raman spectra of the solid cim with Co(II), Cu(II), Ni(II) and Zn(II) metal complexes show that they can adopt two different structures: one is octahedral and the other, with Zn(II), is probably tetrahedral. The octahedral structure appears to be distorted both by the different metal ions as well as by the different anion present. The study was extended to very dilute solutions (ppm range) by using the surface‐enhanced Raman scattering (SERS) technique, mimicking the physiological concentrations of cim and its metal complexes. SERS spectra suggest that, upon the binding of cim to silver colloids, the formation of stable 1:2 cim–metal complexes is excluded, the formation of 1:1 adduct appearing more probable; in this product the metal reaches i...
The adsorption effect of proteins on liposomal bilayer membranes plays a noticeable role in the u... more The adsorption effect of proteins on liposomal bilayer membranes plays a noticeable role in the use of liposomes as drug delivery systems. To explain th\uecs behaviour and correlate it with the protein properties, the thermal behaviour the hydrated multilamellar vesicles (liposomes) of dimyristoylphosphatidylcholine (DMPC) in the presence of increasing amounts of both lysozyme (Lyso) and bovine serum albumine (BSA) at pH = 7.0 was studied by means of Differential Scanning Calorimetry (DSC) technique. Liposomes were prepared mixing DMPC with the protein/water mixtures to a final lipid concentration of about 20% w/w and then incubated 1h at 37\ub0C. DSC scans were performed by a Mettler-Toledo DSC 821C calorimeter at a heating rate of 2.0\ub0C/min. In the samples with the lower Lyso concentrations (up to 2% w/w), a small decrease of about 0.2\ub0C on the main transition temperature (Tm) was observed, whereas Tm increased from 23.3 up to 24.1\ub0C by further addition of the Lyso amount (up to 15%). Contemporaneously, a increase of about 25% on the AH of the transition was observed. The pretransition was affected in a greater extent by the protein presence. Indeed, Tpr, after a small decrease of about 0.5 \ub0C in the 2% Lyscontaining sample, increased from 12.8 to U.4\ub0C in the 15% Lyso-containing samples, with a contemporary 35% increase in the associated AH value. In the presence of BSA a smaller increase (from 23.3 to 23.6\ub0C) in the Tm values was observed, in addition to a contemporary increase of about 10% in the associated AH. On the contrary, at the same conditions, a greater Tpr increase (from 12.8 to 15.2'C) took place. The data suggest that the interaction BSA-liposome involve only the external surface of the bilayer, excluding thus any penetration into the liposomial hydrophobic core. On the contrary, in the presence of Lyso, a partial penetration into the bilayer cannot be excluded, as suggested from the low Tm and Tpr decrease observed in the lower Lyso-containing samples. In the presence of both considered protein the overall bilayer structure of DMPC liposomes is strengthened, suggesting a decrease in the membrane permeability
Poly(epsilon-caprolactone) (PCL), an aliphatic polyester, has received much attention because of ... more Poly(epsilon-caprolactone) (PCL), an aliphatic polyester, has received much attention because of its possible application as both a biocompatible and a biodegradable material. For biomedical purposes, PCL-based products can be used as drug delivery systems to the human body or tissue engineering scaffold material. In the latter case the three dimensional synthetic scaffolds, implanted at the tissue defect site, provide a frame-work for cells to attach, proliferate and form extra cellular matrix. To enhance bone regeneration process, hydroxyapatite (HA), the main component of the inorganic phase of bone, is generally added to the polymer material. Response of the organism to the implanted composite biomaterial depends on numerous factors, one of the most important is sterilisation. Different procedures can be utilised for sterilisation, among them high energy radiations present many benefits. In fact, because of excellent penetration characteristics of ionising radiations, radiation sterilisation eliminates problems associated with residual and ethylene oxide gas penetration, uniformity of sterilisation, etc. The doses for radiation sterilization for medical devices and health care products are established by procedures defined in standard ISO 11137. For tissue allografts, international tissue bank standard recommended 15 kGy* as a minimum dose for bacteria decontamination and 25 kGy as minimum dose for bacteria sterilization. These doses should be validated using procedures established by ISO 11137. Other international tissue banks recommended dose up to 35 kGy. However, high-energy radiation, in addition killing bacterial life, may also affect material properties and the interaction between the different phase of the material. This study was aimed at evaluating possible irradiation-induced effects on morphological and thermal properties of both inorganic and polymeric components of some PCL-HA composites. To this purpose PCL-HA samples with different PCL/HA ratios were exposed to gamma radiations. The sample irradiation was performed at 50 kGy, dose greater than the recommended sterilization dose range under N2 or air atmosphere. The samples were investigated by vibrational spectroscopy (IR and Raman spectroscopies) coupled to thermal analysis measurements (Differential Scanning Calorimetry and Thermogravimetry) which revealed to be highly sensible to structure variations
DOT (2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane) was a widely used chlorinated pesticide. It i... more DOT (2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane) was a widely used chlorinated pesticide. It is characterized by a high environmental persistence time and accumulation in the fat tissues of living organisms. Furthermore, like other lipophilic substances, it can interact with biomembranes inducing membrane structure modification which could play a role both in the transport to the target tissues as well in the development of the toxicity. To this purpose we studied by means of Differential Scanning Calorimetry (DSC) the hydrated multilamellar liposomes of both Dimyristoyl phosphatidylcholine (DMPC) and Dimyristoyl phosphatidyletanolamine (DMPE) in the presence of increasing amounts of DOT. Liposomes were prepared by mixing the appropriate amount of DMPC and DMPE in a NaCI 0.9 % w/w solution up to a final lipid concentration of about 20 % w/w. DSC scans were performed at a heating rate of 2.0\ub0C/min in the thermal ranges of 5-40\ub0C and 25-60\ub0C for DMPC and DMPE samples respectively. The results on DDT/DMPC liposomes show significant Tm decrease and half width increase. The changes, more evident at low DDT concentration (up to 5.0 % w/w) suggest that the hydrophobic core is strongly affected by the presence of DDT molecules, their deep penetration into the bilayer are only partially prevented by the potar interactions between th\ue8 C-CI;i group and the DMPC polar head. In the presence of a greater DMPC amount, the Tm stays unchanged and half width increase slowly suggesting that the DDT solubility into the hydrophobic lipidic bilayer is limited. On the contrary DDT/DMPE liposomes show the presence of a phase segregation that takes piace in the presence of very small amount of DDT. This findings suggest that the DDT molecules interact mainly with th\ue8 outer face of the bilayer and only secondly with the inner hydrophobic core as consequence of the setting up of strong polar interactions involving the more polar head group of DMPE head groups. Also in the high concentrated DDT/DMPE mixtures (DDT > 5.0 % w/w), the shape of the thermograms does not change, confirming the DDT limited solubility into the bilayer
Membrane lipids play an important role in maintaining the normal function and structure of biomem... more Membrane lipids play an important role in maintaining the normal function and structure of biomembranes in plant and animal cells. Studies with some herbicides indicate that these substances interfere with plant membrane functions. The s-triazine herbicides, such as N,N’-Bis (l-methylethyl)-6-methyl-thio-l,3,5-triazine-2,4-diamine (prometryn), are widely used in agriculture; previous investigations have supported the idea biomembranes may be the primary targets of their action.
Raman spectra of avidin, biotin and the avidin‐biotin complex were recorded. The percentages of s... more Raman spectra of avidin, biotin and the avidin‐biotin complex were recorded. The percentages of secondary structure of avidin and the avidin‐biotin complex were obtained from the Raman spectra. The vibrational results indicate that, as a consequence of the interaction of avidin with biotin, the β‐sheet conformation percentage decreases and the α‐helical conformation percentage increases. Moreover, the interaction of avidin with biotin is also able to change slightly the tertiary structure of the protein. In fact, as a consequence of the binding of biotin, the hydrophobicity of the environment of Trp increases slightly according to the intensity increase of the 1360 cm−1 component. The intesity of all bands attributable to Trp residues increases with biotin binding, indicating that Trp is directly involved in the interaction. These results are in agreement with the results of UV measurements which indicate a red shift of the avidin Trp absorption bands as a consequence of the binding to biotin.
Luteolin (LUT) is a polyphenolic compound, found in a variety of fruits, vegetables, and seeds, w... more Luteolin (LUT) is a polyphenolic compound, found in a variety of fruits, vegetables, and seeds, which has a variety of pharmacological properties. In the present contribution, binding of LUT to human serum albumin (HSA), the most abundant carrier protein in the blood, was investigated with the aim of describing the binding mode and parameters of the interaction. The application of circular dichroism, UV-Vis absorption, fluorescence, Raman and surface-enhanced Raman scattering spectroscopy combined with molecular modeling afforded a clear picture of the association mode of LUT to HSA. Specific interactions with protein amino acids were evidenced. LUT was found to be associated in subdomain IIA where an interaction with Trp-214 is established. Hydrophobic and electrostatic interactions are the major acting forces in the binding of LUT to HSA. The HSA conformations were slightly altered by the drug complexation with reduction of alpha-helix and increase of beta-turns structures, suggesting a partial protein unfolding. Also the configuration of at least two disulfide bridges were altered. Furthermore, the study of molecular modeling afforded the binding geometry.
The harmful effects of oxidative processes in living organisms can be reduced by the dietary inta... more The harmful effects of oxidative processes in living organisms can be reduced by the dietary intake of flavonoids, a class of phenolic compounds ubiquitous in plants and widely found in a number of fruits, vegetables and beverages. Many fruits and vegetables are treated by irradiation to solve preservation problems and a radical-induced degradation of nutrients, including polyphenols, may occur. The free radical chemistry of two abundant flavonoids in food, catechin and quercetin, have been investigated by using pulse radiolysis technique. The central role of the phenoxyl-type radical and the strong influence of the state of protonation of the compounds on the pathway of formation and decay of the corresponding oxidized radicals has been evidenced from the spectral properties and chemical reactivity of the radicals derived from the attack of several oxidizing species (⋅OH, N3⋅ SO4−⋅).
The proposed curative properties of Cu-based nonsteroidal anti-inflammatory drugs (NSAIDs) have l... more The proposed curative properties of Cu-based nonsteroidal anti-inflammatory drugs (NSAIDs) have led to the development of numerous Cu(II) complexes of NSAIDs with enhanced anti-inflammatory activity. Crystalline complexes, Cu(II)-NSAID (ibuprofen, naproxen, tolmetin, and diclofenac), with a carboxylic function have been studied by means of infrared and Raman spectroscopy. All NSAIDs bind the metal through the carboxylate group. On the basis of the comparison between the wavenumber of the COO(-) group vibrations and Delta nu (nu(asimm)COO(-) - nu(simm)COO(-)) between Na salts and Cu(II) complexes, conclusions on the probable structure of the complexes have been drawn. The spectroscopic data support the formation of dimeric [Cu(2)L(4)(H(2)O)(2)] complexes in which the COO(-) group behaves as a bridging bidentate ligand. The low wavenumber region of the Raman spectrum provided information on Cu-O and Cu-Cu bonds in the complexes. Thermogravimetric results gave further support to the vibrational data
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Papers by Armida Torreggiani