Low-noise surfaces have become a common mitigation action in the last decade, so much so that different methods for feature extraction have been established to evaluate their efficacy. Among these, the Close Proximity Index (CPX) evaluates the noise emissions by means of multiple runs at different speeds performed with a vehicle equipped with a reference tire and with acoustic sensors close to the wheel. However, signals acquired with CPX make it source oriented, and the analysis does not consider the real traffic flow of the studied site for a receiver-oriented approach. These aspects are remedied by Statistical Pass-By (SPB), a method based on sensor feature extraction with live detection of events; noise and speed acquisitions are performed at the roadside in real case scenarios. Unfortunately, the specific SPB requirements for its measurement setup do not allow an evaluation in urban context unless a special setup is used, but this may alter the acoustical context in which the measurement was performed. The present paper illustrates the testing and validation of a method named Urban Pass-By (U-SPB), developed during the LIFE NEREiDE project. U-SPB originates from standard SPB, exploits unattended measurements and develops an in-lab feature detection and extraction procedure. The U-SPB extends the evaluation in terms of before/after data comparison of the efficiency of low-noise laying in an urban context while combining the estimation of long-term noise levels and traffic parameters for other environmental noise purposes, such as noise mapping and action planning.

The aim of this paper is to present and characterize Polyamidoamine-based hydrogels (PAA) as scaffolds to host photoactive Chlorophyll a (Chl a) from Spirulina (Arthrospira platensis) sea-weed Extract (SE), for potential applications in Photodynamic Therapy (PDT). The pigment extracted from SE was blended inside PAA without further purification, according to Green Chemistry principles. A comprehensive investigation of this hybrid platform, PAA/SE-based, was thus performed in our laboratory and, by means of Visible absorption and emission spectroscopies, the Chl a features, stability and photoactivity were studied. The obtained results evidenced the presence of two main Chl a forms, monomeric and dimeric, interacting with hydrogel polyamidoamines network. To better understand the nature of this interaction, the spectroscopic investigation of this system was performed both before and after the solidification of the hydrogel, that occurred at least in 24 h. Then, focusing the attention on solid scaffold, the Chl a fluorescence lifetime and FTIR-ATR analyses of PAA/SE were carried out, confirming the findings. The swelling and Point Zero Charge (PZC) measurements of solid PAA and PAA/SE were additionally performed to investigate the hydrogel behavior in water. Chl a molecules blended in PAA were (photo) stable and photoactive, and this latter feature was demonstrated showing that the pigment induced, when swelled in water and under irradiation, the formation of singlet oxygen (O), measured by direct and indirect methods.

This study was developed inside the European Project Life "Clean up" (LIFE 16 ENV/ES/000169) to search for suitable adsorbents to purify treated water from emerging pollutants. Notably, among pollutants, the attention was focused on Ciprofloxacin removal, selecting as recyclable adsorbent Cyclodextrin-based nanosponges, characterized by using FTIR-ATR, DSC, TG, SEM, EDX, gas-volumetric analysis, and XRD analyses. Indeed, the in-batch adsorption process was quite complete removing, in a few minutes, 90% of the pollutant from water, with a maximum adsorption capacity of 2 mg/g. A better comprehension of the adsorption mechanism was obtained by studying the effect of various experimental parameters on the process, i.e. ionic strength, pH values, adsorbent/pollutant ratio, and temperature values. The thermodynamics (?G°<0 ?H°<0 and ?S°>0), the adsorption isotherms (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich), and kinetics of the process were also investigated. In particular, the applicability of all the proposed isotherms, except the Langmuir model, was observed, and the finding highlighted the heterogeneous character of the adsorption process. The pseudo-second-order kinetic model well described the process and the application of the Weber-Morris model suggested that two main consecutive steps constituted the adsorption. Despite the relatively low adsorption capacity, desorption experiments, recycling 80% of the pollutant for each cycle, were performed, and for the purpose, 0.1 M NaCl was used, lowering the environmental impact. Moreover, other contaminants, such as Diclofenac, Carbendazim, Furosemide, and Sulfamethoxazole were successfully removed from the water, also if present in a quaternary mixture, opening the possibility to use this adsorbent for real water treatments.

The effect of the exposure of the photosynthetic reaction center from the purple bacterium Rhodobacter sphaeroides to ethylenediamine (EDA) was investigated by transient absorption spectroscopy and UV-Visible-Near Infrared absorption spectroscopy. We show that EDA is not detrimental to the photoactivity of the protein even at pH close to 12. EDA instead appears to inhibit the secondary quinone binding site with an apparent binding constant of 19.05 mM(-1).

Food quality is of paramount importance for public health safety. For instance, fish freshness can be assessed by sensing the volatile short chain alkylamines produced by spoiled fish. Functionalized graphene is a good candidate for the design of gas sensors for such compounds and therefore of interest as the basic material in food quality sensor devices. To shed theoretical insight in this direction, in the present work we investigateviafirst-principles density functional theory (DFT) simulations: (i) graphene functionalizationviaaziridine appendages and (ii) the adsorption of short chain alkylamines (methylamine MA, dimethylamine DMA, and trimethylamine TMA) on the chemically functionalized graphene sheets. Optimal geometries, adsorption energies, and projected density of states (PDOS) are computed using a DFT method. We show that nitrene reactive intermediates, formed by thermal or photo splitting of arylazides -p-carboxyphenyl azide (1a),p-carboxyperfluorophenyl azide (1b), andp-nitrophenyl azide (1c) - react with graphene to yield functionalized derivatives, with reaction energies >-1.0 eV and barriers of the order of 2.0 eV, and open a ~0.3 to 0.5 eV band gap which is in principle apt for applications in sensing and electronic devices. The interaction between the amines and functionalized graphene, as demonstrated from the calculations of charge density differences showing regions of charge gain and others of charge depletion between the involved groups, occurs through hydrogen bonding with interaction energies ranging from -0.04 eV to -0.76 eV, and induce charge differences in the system, which in the case ofp-carboxyperfluorophenyl azide (1b) are sizeable enough to be experimentally observable in sensing.

Acidolysis in conjunction with stabilization of reactive intermediates has emerged as one of the most powerful methods of lignin depolymerization that leads to high aromatic monomer yields. In particular, stabilization of reactive aldehydes using ethylene glycol results in the selective formation of the corresponding cyclic acetals (1,3-dioxolane derivatives) from model compounds, lignin, and even from softwood lignocellulose. Given the high practical utility of this method for future biorefineries, a deeper understanding of the method is desired. Here, we aim to elucidate key mechanistic questions utilizing a combination of experimental and multilevel computational approaches. The multiscale computational protocol used, based on ReaxFF molecular dynamics, represents a realistic scenario, where a typical experimental setup can be reproduced confidently given the explicit molecules of the solute, catalyst, and reagent. The nudged elastic band (NEB) approach allowed us to characterize the key intermolecular interactions involved in the reaction paths leading to crucial intermediates and products. The high level of detail obtained clearly revealed for the first time the unique role of sulfuric acid as a proton donor and acceptor in lignin ?-O-4 acidolysis as well as the reaction pathways for ethylene glycol stabilization, and the difference in reactivity between compounds with different methoxy substituents.

We report a computational study and analysis of the optical absorption and photodecay processes in two subnanometer metal complexes deposited on an oxide support, the regular MgO(100) surface: (i) Ag3(HCO3)(C2H4)2(O) and (ii) Ag3(CO2F)(C2H4)2(O). These aggregates are chosen as derivatives of a Ag3(CO3)(C2H4)2(O) ligand/metal-cluster/support complex, previously singled out as a key intermediate in the path of ethylene partial oxidation to ethylene epoxide catalyzed by Ag3/MgO(100), and serve as model systems to investigate photochemical phenomena in ligand/metal-cluster/support complexes by subnanometer metal catalysts, an appealing field for future research. After generating optimized initial configurations and building cluster models that take properly into account the effect of the charge-separated oxide support, we use time-dependent density-functional theory (TDDFT) to determine first the photoabsorption spectra of the two aggregates and then to follow the evolution of their excited states in the optical region. We show that complexes containing such bicarbonate and fluorocarbonate groups are sensitive to optical adsorption, often leading to ligand detachment and/or cluster disaggregation, thus pointing to an "optical frailty"of these subnanometer cluster species, possibly rationalizing previous experimental observations. Additionally, we correlate the nature of the given excitations and of the corresponding photoinduced reaction products via an analysis of overlap population-density of states (OP-DOS), geometric parameters, and spatial distribution of the molecular orbitals involved in the excitation, thus providing the set of methodological tools needed to explore this novel field.

Bare and ceria-promoted MnO catalysts (0 <= ?<=1) were prepared by redox-precipitation reactions of Mn(VII), Mn(II) and Ce(III) or Ce(IV) precursors in slightly acidic (pH, 4.5) or basic (pH, 8.0) environment to assess genesis, nature, and functionality of surface active sites. Both synthesis protocols yield nanostructured materials with large surface area and exposure of Mn sites, featuring high activity in the CO oxidation and the phenol wet-air-oxidation (CWAO) model reactions (T, 423 K). High oxide dispersion prompts an extensive incorporation of Mn(II) ions into ceria substitutional solid-solution structures, forming oxygen-vacancies with stronger oxidation activity than surface Mn(IV) sites. Basic structure-activity relationships indicate that the superior CO oxidation performance of the pristine ?-MnO system relies on large exposure of very reducible Mn(IV) active sites, while O-adsorption onto Mn(II)/O-vacancy active centres generates very reactive surface oxygen-species boosting the efficiency of composite MnCeO catalysts in the CWAO of phenol.

Abstract: Radiation pressure is used to push gold nanorods on multilayer graphene and create hybrid active surfaces for surface-enhanced Raman spectroscopy (SERS) in liquid. As a proof of concept, ultrasensitive detection of bovine serum albumin is shown and the aggregation kinetics is studied as a function of the irradiation time. We compare the results on graphene with experiments on glass and gold surfaces. Optical aggregation on graphene occurs on time scales of 20 min, ca. 3.5 times slower than on glass. No stable aggregation is obtained on gold. We attribute the differences to the destabilization effect of the standing wave produced on the metallic substrates, due to their higher reflectivity, and to the reduced thermophoretic effects, related to the higher heat dissipation. Despite the slowdown of the aggregation kinetics, the usage of graphene as substrate offers manifold benefits: an almost negligible fluorescence background when using near-infrared light (785 nm), the absence of thermal absorption as well as the possibility to easily functionalize the surface to enhance the affinity with the analytes. Our results enlarge the spectrum of materials that can be used for optical aggregation and SERS detection of biomolecules, highlighting the importance of controlling the physical properties of the surfaces. Graphic abstract: [Figure not available: see fulltext.]

Cylindrical vector beams are used to improve back scattering detection in photonic force microscopy measurements near a dielectric surface. We compare back focal plane interferometry signals acquired on a quadrant photodiode when optical trapping a latex microparticle with gaussian, radial, and azimuthal beams. We find a consistent reduction of the interference pattern generated by the superposition of light backscattered by the trapped particle and backreflected by the dielectric surface. We contrast experimental findings with a model based on light scattering theory in the T - matrix formalism. (C) 2020 Elsevier Ltd. All rights reserved.

The construction from scratch of artificial cells by means of a "bottom up" approach is one of the most ambitious challenges in synthetic biology. Artificial cells capable of imitating the light phase of photosynthesis can be considered photoautotrophs. In bacterial photosynthesis, the first step in the light energy transduction process is the enzymatic photo-redox cycle catalysed by two membrane protein complexes, that is, the photosynthetic reaction centre (RC) and the ubiquinol oxidase (bc1(B)). In this work we studied this process in a micellar suspension of both proteins but coupling a bacterial RC with an ortholog bc1 extracted from mammalian mitochondria (bc1(M)). With this hybrid protein complex chain, the light transduction efficiency turns out to be enhanced up to 90 % by tuning the enzymatic level ratio of the two protein complexes. These results pave the way towards the reconstitution of the entire photosynthetic machinery in artificial membranes for the realization of photoautotrophic artificial cells.

Chiral porphyrin hetero-aggregates, produced from meso-tetrakis(4-N-methylpyridyl) porphyrin H(2)T4 and copper(II) meso-tetrakis(4-sulfonatophenyl)porphyrin CuTPPS by an imprinting effect in the presence of L-3,4-dihydroxyphenylalanine (L-DOPA), are shown herein to serve as templates for the generation of chiral structures during the oxidative conversion of the amino acid to melanin. This remarkable phenomenon is suggested to involve the initial role of L-DOPA and related chiral intermediates like dopachrome as templates for the production of chiral porphyrin aggregates. When the entire chiral pool from DOPA is lost, chiral porphyrin hetero-aggregate would elicit axially chiral oligomer formation from 5,6-dihydroxyindole intermediates in the later stages of melanin synthesis. These results, if corroborated by further studies, may open unprecedented perspectives for efficient strategies of asymmetric melanin synthesis with potential biological and technological applications.

In this work, for the first time, snail slime from garden snails "Helix Aspersa Müller", has been used to induce the formation of eco-friendly gold nanoparticles (AuNPs-SS) suitable for biomedical applications. An AuNPs-SS comprehensive investigation was performed and AuNPs with an average particle size of 14 ± 6 nm were observed, stabilized by a slime snail-based organic layer. Indeed, as recognized in high-resolution MALDI-MS analyses, and corroborated by FESEM, UV-Vis, ATR-FTIR, and XPS results, it was possible to assess the main presence of peptides and amino acids as the main components of the slime, that, combined with the AuNPs confers on them interesting properties. More specifically, we tested, in vitro, the AuNPs-SS safety in human keratinocytes and their potential effect on wound healing as well as their anti-inflammatory properties in murine macrophages. Moreover, the AuNPs-SS treatment resulted in a significant increase of the urokinase-type plasminogen activator receptor (uPAR), essential for keratinocyte adhesion, spreading, and migration, together with the reduction of LPS-induced IL1-? and IL-6 cytokine levels, and completely abrogated the synthesis of inducible nitric oxide synthase (iNOS). This journal is

Carbon dots (CDs) have been progressively attracting interest as novel environmentally friendly and cost-effective luminescent nanoparticles, for implementation in light-emitting devices, solar cells, photocatalytic devices and biosensors. Here, starting from a cost-effective bottom-up synthetic approach, based on a suitable amphiphilic molecule as carbon precursor, namely cetylpyridinium chloride (CPC), green-emitting CDs have been prepared at room temperature, upon treatment of CPC with concentrated NaOH solutions. The investigated method allows the obtaining, in one-pot, of both water-dispersible (W-CDs) and oil-dispersible green-emitting CDs (O-CDs). The study provides original insights into the chemical reactions involved in the process of the carbonization of CPC, proposing a reliable mechanism for the formation of the O-CDs in an aqueous system. The ability to discriminate the contribution of different species, including molecular fluorophores, allows one to properly single out the O-CDs emission. In addition, a mild heating of the reaction mixture, at 70°C, has demonstrated the ability to dramatically decrease the very long reaction time (i.e. from tens of hours to days) at room temperature, allowing us to synthesize O-CDs in a few tens of minutes while preserving their morphological and optical properties.

Pathogenic microorganisms can spread throughout the world population, as the current COVID-19 pandemic has dramatically demonstrated. In this scenario, a protection against pathogens and other microorganisms can come from the use of photoactive materials as antimicrobial agents able to hinder, or at least limit, their spreading by means of photocatalytically assisted processes activated by light--possibly sunlight--promoting the formation of reactive oxygen species (ROS) that can kill microorganisms in different matrices such as water or different surfaces without affecting human health. In this review, we focus the attention on TiO nanoparticle-based antimicrobial materials, intending to provide an overview of the most promising synthetic techniques, toward possible large-scale production, critically review the capability of such materials to promote pathogen (i.e., bacteria, virus, and fungi) inactivation, and, finally, take a look at selected technological applications.

A novel hybrid nanocomposite, formed of Reduced Graphene Oxide (RGO) flakes surface functionalized with 1-pyrene carboxylic acid (PCA) and decorated by Au nanoparticles (NPs), has been synthesized for the electrochemical detection of the miRNA-221 cancer biomarker. The hybrid material has been prepared by a facile approach, relaying on the in situ synthesis of the Au NPs onto the PCA carboxylic groups in presence of 3,4-dimethylbenzenethiol (DMBT) and NaBH. The short aromatic thiol DMBT acts as reducing and coordinating agent, and hence, enables the dispersion of the nanocomposite in organic solvents. Concomitantly, DMBT favors the non-covalent anchoring of the Au NPs onto RGO, potentially allowing an efficient particle/RGO and interparticle ?-? mediated electron coupling, which enhances the electron conductivity and charge transfer. PCA-RGO flakes, densely and uniformly decorated with a multilayer network of DMBT-coated Au NPs, 2.8 ± 0.6 nm in size, have been obtained, overcoming limitations previously reported for similar hybrid materials in terms of coating density and NP size distribution. Screen-Printed Carbon Electrodes (SPCEs), modified by the hybrid material and then functionalized with a thiolated DNA capture probe, have been tested for the determination of miRNA-221 in spiked human serum samples.

Quantum dots (QDs) have extraordinary strong light absorption and size tunable bandgap. However, QD films are typically limited to ~200-300 nm due to their poor charge mobility. This severely limits the quantum efficiency of QD devices for ? <750 nm (infrared). Herein, we report a record 1 ?m thick QD film using intercalated graphene layers as transparent current extractors. This overcomes QD poor mobility, ensuring both effective light absorption and charge extraction towards the near-infrared reaching quantum efficiency (EQE) of 90%. The short diffusion length (LD<200 nm) of QDs limits their useful thickness to ~200-300 nm1-4, resulting in poor infrared light absorption. To overcome this limitation, we have built a 1 ?m thick QD film with intercalated transparent graphene electrodes that keep high charge collection efficiency. As a result, the 1 ?m intercalated devices show a superior EQE reaching 90% at ? ~800 nm without the drop of quantum efficiency at ? ~700 nm observed in most QD devices. The EQE of intercalated devices improves over the entire ?~ 600-1100 nm spectrum as the thickness increases from 100 nm to 1 ?m, clearly breaking the restriction that the diffusion length of QDs imposes on the film thickness. This improves absorption and charge collection in the infrared.

aser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS) is a powerful and well-established analytical technique, withhigh sensitivity and fast response, extensively applied to investigateinorganic elements in solid specimen [1-3]. Little or no sample pre-paration is required and analyses can be performed on a large range ofmaterials: conducting, non-conducting, opaque and transparent. Thesample mass size required is in the order of sub-micrograms, whichessentially keeps the item aspect unaltered. It can be applied to dif-ferent analysis approaches: from bulk analysis and depth profiling toelemental/isotope mapping.All these advantages make the technique both extremely versatileandflexible, so it is currently applied in various scientificfields, such asbiology, metallurgy, archeology, material science, geology, etc.Nevertheless, LA-ICPMS cannot be considered as a direct all-purposetechnique to be applied any solid item due to some issues: the aerosolsample composition is not always perfectly representative, transportefficiency is problematic and there may be a possible incomplete de-composition of particles that reach the ICP.Studies to improve LA-ICPMS instrumentation and quantificationstrategies are still ongoing. The biggest challenge regards elementalfractionation, which is related to abundances of detected ions, fre-quently not stoichiometrically corresponding to the composition of thepristine sample [1-5]. In the aerosol, differing sizes and geometry ofparticles ablated from different matrices represent another importantissue to be investigated and is related to the laser-sample interactionwhich affects sample transport efficiency from the ablation cell to theplasma and the subsequent atomization of particles in the ICP.Various efforts have been carried out to control these issues[1, 6-20]. Most studies have investigated the effect of instrumentalparameters on aerosol formation. In particular, the influence of bothlaser wavelength and pulse duration on the formation of a homo-geneous aerosol have been extensively monitored.Recently, the use of metallic nanoparticles (NPs) has been proposedto improve the efficiency of energy transfer from the ns-laser pulse tothe sample in Laser Induced Breakdown Spectroscopy (LIBS), namelyNELIBS [21]. In these works, an improvement of the LOD up to 2 ordersof magnitude has been found. LIBS and LA-ICPMS are clearly two dif-ferent analytical approaches, as thefirst is based on the direct ob-servation of the laser induced plasma, while the latter also involves thetransportation of the aerosol to the ICP torch, its atomization and io-nization. In any case, both techniques are based on the same sampleoperation, i.e. the laser ablation, so the use of NPs deposited on thesurface can improve, although in a different extent, LA-ICPMS too.Recently, the feasibility of enhancing the LA-ICPMS signal of major andminor elements in Al alloy and brass by Ag and Au NPs was proven [22]but many questions remain unanswered. In this paper a detailed char-acterization of the processes occurring during NELA-ICPMS (Nano-particle-Enhanced LA-ICPMS) is proposed, in order to improve itsgeneral performance. Inside this framework, the effects of NP size andtype(i.e. Au, Ag, Pt), with specific SPR (Surface Plasmon Resonance),on the signal enhancement of a large variety of trace elements, both inconductive and dielectric matrices, were tested. The obtained resultsopen the way to several fundamental issues concerning both NPs' en-hanced photoablation and the consequent effect of NPs on particleformation and the subsequent stages (transport, ionization, atomiza-tion).Although further studies are still required to obtain a completeunderstanding of the effect of the use of NPs in LA-ICPMS, this paperaims to provide a general idea of the perspectives of NELA-ICPMS in-vestigating the effect of NPs during ablation and subsequent transportin the ICP torch, in order to extend knowledge on the causes of theenhancement of the signal of some trace elements in a standard sample

Grapes contain many flavonoid and non-flavonoid compounds with anticancer effects. In this work we fully characterized the polyphenolic profile of two grape skin extracts (GSEs), Autumn Royal and Egnatia, and assessed their effects on Polyunsaturated Fatty Acid (PUFA) membrane levels of Caco2 and SW480 human colon cancer cell lines. Gene expression of 15-lipoxygenase-1 (15-LOX-1), and peroxisome proliferator-activated receptor gamma (PPAR-gamma), as well as cell morphology, were evaluated. The polyphenolic composition was analyzed by Ultra-High-Performance Liquid Chromatography/Quadrupole-Time of Flight mass spectrometry (UHPLC/QTOF) analysis. PUFA levels were evaluated by gas chromatography, and gene expression levels of 15-LOX-1 and PPAR-gamma were analyzed by real-time Polymerase Chain Reaction (PCR). Morphological cell changes caused by GSEs were identified by field emission scanning electron microscope (FE-SEM) and photomicrograph examination. We detected a different profile of flavonoid and non-flavonoid compounds in Autumn Royal and Egnatia GSEs. Cultured cells showed an increase of total PUFA levels mainly after treatment with Autumn Royal grape, and were richer in flavonoids when compared with the Egnatia variety. Both GSEs were able to affect 15-LOX-1 and PPAR-gamma gene expression and cell morphology. Our results highlighted a new antitumor mechanism of GSEs that involves membrane PUFAs and their downstream pathways.

The use of controlled delivery therapy in colorectal cancer (CRC) reduces toxicity and side effects. Recently, we have suggested that the Frizzled 10 (FZD10) protein, a cell surface receptor belonging to the FZD protein family that is overexpressed in CRC cells, is a novel candidate for targeting and treatment of CRC. Here, the anticancer effect of novel immuno-liposomes loaded with 5-Fluorouracil (5-FU), decorated with an antibody against FZD10 (anti-FZD10/5-FU/LPs), was evaluated in vitro on two different CRC cell lines, namely metastatic CoLo-205 and nonmetastatic CaCo-2 cells, that were found to overexpress FZD10. The anti-FZD10/5-FU/LPs obtained were extensively characterized and their preclinical therapeutic efficacy was evaluated with the MTS cell proliferation assay based on reduction of tetrazolium compound, scratch test, Field Emission Scanning Electron Microscopes (FE-SEM) investigation and immunofluorescence analysis. The results highlighted that the cytotoxic activity of 5-FU was enhanced when encapsulated in the anti-FZD10 /5-FU/LPs at the lowest tested concentrations, as compared to the free 5-FU counterparts. The immuno-liposomes proposed herein possess a great potential for selective treatment of CRC because, in future clinical applications, they can be encapsulated in gastro-resistant capsules or suppositories for oral or rectal delivery, thereby successfully reaching the intestinal tract in a minimally invasive manner.