This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,t...This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts.展开更多
Intrinsically disordered proteins, such as tau or α-synuclein, have long been associated with a dysfunctional role in neurodegenerative diseases. In Alzheimer’s and Parkinson’s’ diseases, these proteins, sharing a...Intrinsically disordered proteins, such as tau or α-synuclein, have long been associated with a dysfunctional role in neurodegenerative diseases. In Alzheimer’s and Parkinson’s’ diseases, these proteins, sharing a common chemical-physical pattern with alternating hydrophobic and hydrophilic domains rich in prolines, abnormally aggregate in tangles in the brain leading to progressive loss of neurons. In this review, we present an overview linking the studies on the implication of the peptidyl-prolyl isomerase domain of immunophilins, and notably FKBP12, to a variety of neurodegenerative diseases, focusing on the molecular origin of such a role. The involvement of FKBP12 dysregulation in the aberrant aggregation of disordered proteins pinpoints this protein as a possible therapeutic target and, at the same time, as a predictive biomarker for early diagnosis in neurodegeneration, calling for the development of reliable, fast and cost-effective detection methods in body fluids for community-based screening campaigns.展开更多
We have previously shown that the diphtheria toxin variant CRM 197 （cross-reacting material 197） can be overexpressed in Escherichia coli at high levels, yielding insoluble aggregates, which were solubilized using u...We have previously shown that the diphtheria toxin variant CRM 197 （cross-reacting material 197） can be overexpressed in Escherichia coli at high levels, yielding insoluble aggregates, which were solubilized using urea. This study reports a comparison of three matrices suitable for the purification and refolding of recombinant CRM197 by metal-chelating affinity chromatography, Moreover, we show that refolded CRM197 features enzymatic activity.展开更多
During the last decade,perovskite solar technologies underwent an impressive development,with power conversion efficiencies reaching 25.5%for single-junction devices and 29.8%for Silicon-Perovskite tandem configuratio...During the last decade,perovskite solar technologies underwent an impressive development,with power conversion efficiencies reaching 25.5%for single-junction devices and 29.8%for Silicon-Perovskite tandem configurations.Even though research mainly focused on improving the efficiency of perovskite photovoltaics(PV),stability and scalability remain fundamental aspects of a mature photovoltaics technology.For n-i-p structure perovskite solar cells,using poly-triaryl(amine)(PTAA)as hole transport layer(HTL)allowed to achieve marked improvements in device stability compared with other common hole conductors.For p-i-n structure,poly-triaryl(amine)is also routinely used as dopant-free hole transport layer,but problems in perovskite film growth,and its limited resistance to stress and imperfect batch-to-batch reproducibility,hamper its use for device upscaling.Following previous computational investigations,in this work,we report the synthesis of two small-molecule organic hole transport layers(BPT-1,2),aiming to solve the above-mentioned issues and allow upscale to the module level.By using BPT-1 and methylammonium-free perovskite,max.Power conversion efficiencies of 17.26%and 15.42%on a small area(0.09 cm^(2))and mini-module size(2.25 cm^(2)),respectively,were obtained,with a better reproducibility than with poly-triaryl(amine).Moreover,BPT-1 was demonstrated to yield more stable devices compared with poly-triaryl(amine)under ISOS-D1,T1,and L1 accelerated life-test protocols,reaching maximum T_(90)values>1000 h on all tests.展开更多
Herein,we report on the successful encapsulation into human H-ferritin of two highly charged Ru(Ⅱ)polypyridyl complexes,[Ru(phen)2L’]^(2+)(Ru1,with L’=4,4’-(2,5,8,11,14-pentaaza[15])-2,2’-bipyridilophane)and[Ru(p...Herein,we report on the successful encapsulation into human H-ferritin of two highly charged Ru(Ⅱ)polypyridyl complexes,[Ru(phen)2L’]^(2+)(Ru1,with L’=4,4’-(2,5,8,11,14-pentaaza[15])-2,2’-bipyridilophane)and[Ru(phen)2L’’]^(2+)(Ru2,with L’’=4,4’-bis-[methylen-(1,4,7,10-tetraazacyclododecane)]-2,2’-bipyridine).The resulting Ru(Ⅱ)-ferritin nanocomposites are highly luminescent,display great stability in physiological conditions and preserve the native shell–core structure of the protein.Moreover,the singlet oxygen sensitizing properties of metal complexes,established by independent spectrophotometric and spectrofluorimetric measurements,are largely maintained also in their encapsulated form.Ru(Ⅱ)-ferritin nanocomposites are exclusively internalized by cancer cells expressing the transferrin receptor 1(TfR1)(i.e.HeLa and A2780 with respect to non-cancerous C2C12 myoblasts).Immunofluorescence analysis also reveals the co-localization of Ru1 and Ru2 with the TfR1 in the internal cellular compartments of HeLa and A2780 cells,highlighting the crucial role played by the receptor-mediated endocytosis of H-type ferritins exerted by TfR1.Finally,an MTT assay probed that light-activation effectively leads to a marked dose-dependent cytotoxic effect uniquely against cancer cells.This study underlines the potential of human H-ferritin as a valuable tool for the tumor-targeted delivery of sensitizing agents for photodynamic therapy.展开更多
In photodynamic therapy(PDT),Ru(Ⅱ)polypyridyl complexes(RPCs)featuring the popularπ-expansive benzo[i]dipyrido[3,2-a:2’,3’-c]phenazine(dppn)ligand have attracted much attention,mainly due to the good singlet oxyge...In photodynamic therapy(PDT),Ru(Ⅱ)polypyridyl complexes(RPCs)featuring the popularπ-expansive benzo[i]dipyrido[3,2-a:2’,3’-c]phenazine(dppn)ligand have attracted much attention,mainly due to the good singlet oxygen sensitizing properties imparted by this peculiar ligand.However,notwithstanding the intriguing perspectives,much remains to be explored about the use of RPC-based photosensitizing agents(PSs)with more than a dppn ligand in their scaffolds.展开更多
The excellent ability of dye-sensitized solar cells(DSSCs)to capture ambient light and convert it into electric current makes them attractive power sources for indoor applications,including powering Internet of Things...The excellent ability of dye-sensitized solar cells(DSSCs)to capture ambient light and convert it into electric current makes them attractive power sources for indoor applications,including powering Internet of Things(IoT)devices.In this context,substantial research efforts have been devoted to the discovery of novel organic dyes able to harvest energy from a wide range of indoor light sources at different intensities.However,such activities are often based on trial-and-error procedures which are frequently expensive and time-consuming.Here,Machine Learning(ML)techniques and Density Functional Theory(DFT)methods have been combined in a two-stage approach,with the aim to accelerate the design of new,synthetically accessible organic dyes for indoor DSSC applications.By predicting the power conversion efficiency(PCE)under different indoor light sources and intensities,potentially high-performance organic dyes have been identified.展开更多
Cultural heritage assets constitute a fundamental socioeconomic resource,but the actual works of art need to be maintained,counteracting degradation processes,to transfer these benefits to future generations.In partic...Cultural heritage assets constitute a fundamental socioeconomic resource,but the actual works of art need to be maintained,counteracting degradation processes,to transfer these benefits to future generations.In particular,the removal of soil,aged coatings,and vandalism/overpaints is one of the most needed interventions in art restoration.Traditional cleaning methodologies,based on classical solution and polymer chemistry,only grant limited control of the cleaning interventions,with the risk of affecting the original components of the artifacts,and often involving the use of toxic or non-environmentally friendly compounds.Alternatively,materials science,colloids,and soft matter have provided valuable and safe solutions in the last decades.This review provides a selection of the most recent and advanced methodologies for the wet cleaning of works of art,spanning from nanostructured cleaning fluids(microemulsions,surfactants swollen micelles)to physical and chemical gels.The new methodologies work on different physico-chemical mechanisms,such as processes for detaching/dewetting,to selectively remove the unwanted layers in sustainable and cost-effective interventions.The best performing systems,like microemulsions confined in“twin-chain”polyvinyl alcohol gels,have been assessed in the cleaning of masterpieces such as works by Pablo Picasso,Jackson Pollock and Roy Lichtenstein.Particular attention is dedicated to“green”chemistry systems,using low-toxicity solvents or bio-based/waste materials to build gel networks.Finally,current trends and future perspectives are given,showing that advanced systems for art cleaning link with transversal fields of crucial importance even beyond Cultural heritage conservation,e.g.,detergency,tissue engineering,drug-delivery,food industry and cosmetics.展开更多
Chromophoric dissolved organic matter(CDOM)strongly influences the water-leaving radiance from aquatic ecosystems.In most inland waters,the remote determination of CDOM absorption presents a central challenge due to t...Chromophoric dissolved organic matter(CDOM)strongly influences the water-leaving radiance from aquatic ecosystems.In most inland waters,the remote determination of CDOM absorption presents a central challenge due to their complex optical conditions.However,identifying the temporal and spatial variability of CDOM is fundamental to the understanding of aquatic biogeo-chemical dynamics.In the present study,semi-analytical and empirical modeling approaches were used to examine CDOM absorption in four,shallow,inland water bodies using the spectral bands and sensitivities of major satellite observational systems.Of the models examined,an empirical multiband model was found to provide the highest correlation with measured CDOM absorption.The spectral characteristics of the MERIS sensors yielded the best results with respect to the other available satellite sensors.High detrital load was observed to be a major impediment to estimating CDOM absorption,while lakes with elevated phytoplankton biomass did not present similar problems.展开更多
The degradation process of cellulose-made materials was investigated by means of nuclear magnetic resonance （NMR） spectroscopy, with particular emphasis on the role of water and on the hydration mechanism of cellulo...The degradation process of cellulose-made materials was investigated by means of nuclear magnetic resonance （NMR） spectroscopy, with particular emphasis on the role of water and on the hydration mechanism of cellulose fibrils. To accomplish this, the structure and dynamics of water within ancient and modern samples with different aging histories were investigated. The results mainly indicated that hydrolytic and oxidative reactions provoked the formation of acidic by-products. Furthermore, degradation processes were enhanced by higher amounts of water giving a progressive consumption of the amorphous regions of the cellulose. We propose NMR experiments as a benchmark for character- ization of the degradation state of paper, as well as for investigating the effectiveness of restoration treatments.展开更多
The modification of amyloid fibrils cytotoxicity through exogenous nanomaterials is crucial to understand the processes controlling the role of protein aggregation in the related diseases.The influence of nanoparticle...The modification of amyloid fibrils cytotoxicity through exogenous nanomaterials is crucial to understand the processes controlling the role of protein aggregation in the related diseases.The influence of nanoparticles on amyloid stability yields great interest due to the small size and high surface area-to-volume ratio of nanoparticles.Various physico-chemical parameters play a role in the interaction of proteins and nanoparticles in solution,thus influencing the disaggregation of preformed fibrils.We have examined the influence of two kinds of metallic nanoparticles on lysozyme amyloid fibrils using a multi-technique approach and focalized their impact on cytotoxicity on human neuroblastoma cells(SH-SY5Y).In particular,fluorescence,infrared and circular dichroism spectroscopies,optical and atomic force microscopy experiments have been carried out;the results are analyzed to rationalize the effects of these complexes on neural cell viability.It is remarkable,that the fibrils in the presence of AuNPs,unlike fibrils alone or with AgNPs,do not generate a significant cytotoxic effect even at high concentration and an amyloid degradation effect is visible.展开更多
Herein we study the different microscopic interactions occurring in water/methanol solutions at dif- ferent methanol molar fractions, using NMR spctroscopy. Temperature was found to determine which interaction dominat...Herein we study the different microscopic interactions occurring in water/methanol solutions at dif- ferent methanol molar fractions, using NMR spctroscopy. Temperature was found to determine which interaction dominates. It was found that the mixing between water and methanol is non-ideal because of the presence of interactions like hydrophobicity and hydrophilicity. These results indicate that the competition between hydrophilic and hydrophobic interactions is different in different thermal regions, and that the physical properties of the solution are determined by the character of the solution itself, which in turn depends on the mole fraction of methanol and on the temperature.展开更多
基金the Italian Ministry of Universities and Research for funding his PhD scholarship(37th Cycle Ph D Programmes supported by ESF REACT-EU funds,National Operational Programme on Research and Innovation)CSGI(Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase-Center for Colloid and Surface Science),Florence(Italy)for financial support.
文摘This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts.
文摘Intrinsically disordered proteins, such as tau or α-synuclein, have long been associated with a dysfunctional role in neurodegenerative diseases. In Alzheimer’s and Parkinson’s’ diseases, these proteins, sharing a common chemical-physical pattern with alternating hydrophobic and hydrophilic domains rich in prolines, abnormally aggregate in tangles in the brain leading to progressive loss of neurons. In this review, we present an overview linking the studies on the implication of the peptidyl-prolyl isomerase domain of immunophilins, and notably FKBP12, to a variety of neurodegenerative diseases, focusing on the molecular origin of such a role. The involvement of FKBP12 dysregulation in the aberrant aggregation of disordered proteins pinpoints this protein as a possible therapeutic target and, at the same time, as a predictive biomarker for early diagnosis in neurodegeneration, calling for the development of reliable, fast and cost-effective detection methods in body fluids for community-based screening campaigns.
文摘We have previously shown that the diphtheria toxin variant CRM 197 （cross-reacting material 197） can be overexpressed in Escherichia coli at high levels, yielding insoluble aggregates, which were solubilized using urea. This study reports a comparison of three matrices suitable for the purification and refolding of recombinant CRM197 by metal-chelating affinity chromatography, Moreover, we show that refolded CRM197 features enzymatic activity.
基金funding from the Italian Ministry of Economic Development(MISE)in the framework of the Operating Agreement with ENEA for Research on the Electric Systemfrom the Italian Ministry of University and Research(MUR)in the framework of“BEST4U”Project,PON R&I 2014-2020.L.V.,M.S.+2 种基金A.D.C.were supported by the European Union's Horizon 2020 Framework Program for funding Research and Innovation under grant agreement no.764047(ESPResSo)no.691664(UNIQUE,Cofund ERANET Action,MUR GA 775970)no.826013(IMPRESSIVE).C.C.and A.S.acknowledge MIUR Grant—Department of Excellence 2018-2022 and the European Union's Horizon 2020 Framework Program for funding Research and Innovation under grant agreement no.764047(ESPResSo).
文摘During the last decade,perovskite solar technologies underwent an impressive development,with power conversion efficiencies reaching 25.5%for single-junction devices and 29.8%for Silicon-Perovskite tandem configurations.Even though research mainly focused on improving the efficiency of perovskite photovoltaics(PV),stability and scalability remain fundamental aspects of a mature photovoltaics technology.For n-i-p structure perovskite solar cells,using poly-triaryl(amine)(PTAA)as hole transport layer(HTL)allowed to achieve marked improvements in device stability compared with other common hole conductors.For p-i-n structure,poly-triaryl(amine)is also routinely used as dopant-free hole transport layer,but problems in perovskite film growth,and its limited resistance to stress and imperfect batch-to-batch reproducibility,hamper its use for device upscaling.Following previous computational investigations,in this work,we report the synthesis of two small-molecule organic hole transport layers(BPT-1,2),aiming to solve the above-mentioned issues and allow upscale to the module level.By using BPT-1 and methylammonium-free perovskite,max.Power conversion efficiencies of 17.26%and 15.42%on a small area(0.09 cm^(2))and mini-module size(2.25 cm^(2)),respectively,were obtained,with a better reproducibility than with poly-triaryl(amine).Moreover,BPT-1 was demonstrated to yield more stable devices compared with poly-triaryl(amine)under ISOS-D1,T1,and L1 accelerated life-test protocols,reaching maximum T_(90)values>1000 h on all tests.
文摘Herein,we report on the successful encapsulation into human H-ferritin of two highly charged Ru(Ⅱ)polypyridyl complexes,[Ru(phen)2L’]^(2+)(Ru1,with L’=4,4’-(2,5,8,11,14-pentaaza[15])-2,2’-bipyridilophane)and[Ru(phen)2L’’]^(2+)(Ru2,with L’’=4,4’-bis-[methylen-(1,4,7,10-tetraazacyclododecane)]-2,2’-bipyridine).The resulting Ru(Ⅱ)-ferritin nanocomposites are highly luminescent,display great stability in physiological conditions and preserve the native shell–core structure of the protein.Moreover,the singlet oxygen sensitizing properties of metal complexes,established by independent spectrophotometric and spectrofluorimetric measurements,are largely maintained also in their encapsulated form.Ru(Ⅱ)-ferritin nanocomposites are exclusively internalized by cancer cells expressing the transferrin receptor 1(TfR1)(i.e.HeLa and A2780 with respect to non-cancerous C2C12 myoblasts).Immunofluorescence analysis also reveals the co-localization of Ru1 and Ru2 with the TfR1 in the internal cellular compartments of HeLa and A2780 cells,highlighting the crucial role played by the receptor-mediated endocytosis of H-type ferritins exerted by TfR1.Finally,an MTT assay probed that light-activation effectively leads to a marked dose-dependent cytotoxic effect uniquely against cancer cells.This study underlines the potential of human H-ferritin as a valuable tool for the tumor-targeted delivery of sensitizing agents for photodynamic therapy.
基金Department of Chemistry Ugo Schiff of the University of Florence for the Cryo-TEM measurements.UniCA-Progetti biennali di Ateno Finanziati dalla Fondazione di Sardegna 2018(CUP F741I19000950007)is gratefully acknowledged for(partial)financial support.
文摘In photodynamic therapy(PDT),Ru(Ⅱ)polypyridyl complexes(RPCs)featuring the popularπ-expansive benzo[i]dipyrido[3,2-a:2’,3’-c]phenazine(dppn)ligand have attracted much attention,mainly due to the good singlet oxygen sensitizing properties imparted by this peculiar ligand.However,notwithstanding the intriguing perspectives,much remains to be explored about the use of RPC-based photosensitizing agents(PSs)with more than a dppn ligand in their scaffolds.
基金the hpc@dbcf for providing computational resources and Regione Toscana for granting the Project INSIEME(Approcci di INtelligenza artificiale,Sintesi Innovative e valutazione di sostenibilitàEconomico-ambientale per lo sviluppo di nuovi Materiali per la conversione e stoccaggio dell’Energia solare)-Progetti di alta formazione-Fondo Sociale Europeo+2021-207(FSE+2021-2027).
文摘The excellent ability of dye-sensitized solar cells(DSSCs)to capture ambient light and convert it into electric current makes them attractive power sources for indoor applications,including powering Internet of Things(IoT)devices.In this context,substantial research efforts have been devoted to the discovery of novel organic dyes able to harvest energy from a wide range of indoor light sources at different intensities.However,such activities are often based on trial-and-error procedures which are frequently expensive and time-consuming.Here,Machine Learning(ML)techniques and Density Functional Theory(DFT)methods have been combined in a two-stage approach,with the aim to accelerate the design of new,synthetically accessible organic dyes for indoor DSSC applications.By predicting the power conversion efficiency(PCE)under different indoor light sources and intensities,potentially high-performance organic dyes have been identified.
基金supported by the CSGIthe European Union(APACHE project,Horizon 2020 research and innovation program)(Grant No.814496)+1 种基金GREENART projectHorizon Europe research and innovation program(Grant No.101060941)。
文摘Cultural heritage assets constitute a fundamental socioeconomic resource,but the actual works of art need to be maintained,counteracting degradation processes,to transfer these benefits to future generations.In particular,the removal of soil,aged coatings,and vandalism/overpaints is one of the most needed interventions in art restoration.Traditional cleaning methodologies,based on classical solution and polymer chemistry,only grant limited control of the cleaning interventions,with the risk of affecting the original components of the artifacts,and often involving the use of toxic or non-environmentally friendly compounds.Alternatively,materials science,colloids,and soft matter have provided valuable and safe solutions in the last decades.This review provides a selection of the most recent and advanced methodologies for the wet cleaning of works of art,spanning from nanostructured cleaning fluids(microemulsions,surfactants swollen micelles)to physical and chemical gels.The new methodologies work on different physico-chemical mechanisms,such as processes for detaching/dewetting,to selectively remove the unwanted layers in sustainable and cost-effective interventions.The best performing systems,like microemulsions confined in“twin-chain”polyvinyl alcohol gels,have been assessed in the cleaning of masterpieces such as works by Pablo Picasso,Jackson Pollock and Roy Lichtenstein.Particular attention is dedicated to“green”chemistry systems,using low-toxicity solvents or bio-based/waste materials to build gel networks.Finally,current trends and future perspectives are given,showing that advanced systems for art cleaning link with transversal fields of crucial importance even beyond Cultural heritage conservation,e.g.,detergency,tissue engineering,drug-delivery,food industry and cosmetics.
基金We gratefully acknowledge the financial support of the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KZCX2-YW-QN311,No.KZCX2-EW-QN308)National Natural Science Foundation of China(Grant No.40871168,No.40801137)the Dragon 3 Projects(ID-10561).
文摘Chromophoric dissolved organic matter(CDOM)strongly influences the water-leaving radiance from aquatic ecosystems.In most inland waters,the remote determination of CDOM absorption presents a central challenge due to their complex optical conditions.However,identifying the temporal and spatial variability of CDOM is fundamental to the understanding of aquatic biogeo-chemical dynamics.In the present study,semi-analytical and empirical modeling approaches were used to examine CDOM absorption in four,shallow,inland water bodies using the spectral bands and sensitivities of major satellite observational systems.Of the models examined,an empirical multiband model was found to provide the highest correlation with measured CDOM absorption.The spectral characteristics of the MERIS sensors yielded the best results with respect to the other available satellite sensors.High detrital load was observed to be a major impediment to estimating CDOM absorption,while lakes with elevated phytoplankton biomass did not present similar problems.
文摘The degradation process of cellulose-made materials was investigated by means of nuclear magnetic resonance （NMR） spectroscopy, with particular emphasis on the role of water and on the hydration mechanism of cellulose fibrils. To accomplish this, the structure and dynamics of water within ancient and modern samples with different aging histories were investigated. The results mainly indicated that hydrolytic and oxidative reactions provoked the formation of acidic by-products. Furthermore, degradation processes were enhanced by higher amounts of water giving a progressive consumption of the amorphous regions of the cellulose. We propose NMR experiments as a benchmark for character- ization of the degradation state of paper, as well as for investigating the effectiveness of restoration treatments.
基金This work was partially supported by Slovak grand agency VEGA 2/0145/17,APW-18-0284,Italian flagship NANOMAX,N-CHEM,Ministery o f Education,University and Research(PRIN grant 20173L7W8K).Microscopy was carried out at the SPM@ISMN facility.
文摘The modification of amyloid fibrils cytotoxicity through exogenous nanomaterials is crucial to understand the processes controlling the role of protein aggregation in the related diseases.The influence of nanoparticles on amyloid stability yields great interest due to the small size and high surface area-to-volume ratio of nanoparticles.Various physico-chemical parameters play a role in the interaction of proteins and nanoparticles in solution,thus influencing the disaggregation of preformed fibrils.We have examined the influence of two kinds of metallic nanoparticles on lysozyme amyloid fibrils using a multi-technique approach and focalized their impact on cytotoxicity on human neuroblastoma cells(SH-SY5Y).In particular,fluorescence,infrared and circular dichroism spectroscopies,optical and atomic force microscopy experiments have been carried out;the results are analyzed to rationalize the effects of these complexes on neural cell viability.It is remarkable,that the fibrils in the presence of AuNPs,unlike fibrils alone or with AgNPs,do not generate a significant cytotoxic effect even at high concentration and an amyloid degradation effect is visible.
文摘Herein we study the different microscopic interactions occurring in water/methanol solutions at dif- ferent methanol molar fractions, using NMR spctroscopy. Temperature was found to determine which interaction dominates. It was found that the mixing between water and methanol is non-ideal because of the presence of interactions like hydrophobicity and hydrophilicity. These results indicate that the competition between hydrophilic and hydrophobic interactions is different in different thermal regions, and that the physical properties of the solution are determined by the character of the solution itself, which in turn depends on the mole fraction of methanol and on the temperature.
