In order to improve knowledge of the identification, distribution and abundances of microplastic particles of 1 mm or less (S-MPPs) in the coastal area of the Mediterranean region, a preliminary ...monitoring survey was carried out in a transitional environment along the north-eastern Italian coasts, the Lagoon of Venice. S-MPPs were evaluated in sediments collected from 10 sites chosen in shallow areas variously affected by natural conditions and anthropogenic influences (i.e., landward stations influenced by freshwater inputs, seaward areas near sea inlets, and sites influenced by the presence of aquaculture farms, industry and city centers). S-MPPs, extracted from bulk sediments by density separation, were counted and identified by Fourier-Transform Infrared Micro-spectroscopy (μFT-IR). The μFT-IR process included automatic surface chemical mapping and references to an infrared library database to identify the compositional spectra of particles. S-MPPs were recovered from all samples – a fact which emphasizes their extensive distribution throughout the Lagoon. Total abundances varied from 2175 to 672 S-MPPs kg−1 d.w., higher concentrations generally being observed in landward sites. Of the ten polymer types identified, the most abundant, accounting for more than 82% of total S-MPPs, were polyethylene and polypropylene. The most frequent size (93% of observed microplastics) was in the range 30–500 μm. Total S-MPP values were significantly correlated with the finer sediment fraction and with the metal pollution index.
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•Microplastics ≤1 mm extracted from bulk sediments were identified by μFT-IR.•Their occurrence and distribution were evidenced in the sediments of Venice Lagoon.•Microplastics were found in all samples, with highest concentrations in landward sites.•The most abundant polymers were polyethylene and polypropylene.
In this paper, among all transduction methodologies reported in the field of solid state chemical sensors, the attention has been focused onto the optical sensing characterization by using surface ...plasmon resonance (SPR) technique and its evolution towards active plasmonics. Activation of the transducer by application of an oscillating magnetic field in a transversal configuration is demonstrated to improve the gas sensing performance of classical SPR sensors. To this purpose a new transducer, composed of metallic and magnetic materials and a proper sensing layer have been chosen. TiO2 sensing layers have been prepared by two different experimental routes and their optical and morphological features investigated and correlated with their sensing performances. A comparison between classical SPR technique and a new sensing probe based onto magneto-plasmonic effect in resonance condition has been reported. Improved gas sensing performance in terms of sensitivity has been demonstrated in the presence of different alcohol vapours concentration mixed in dry air.
Fe3O4/γ-Fe2O3 nanoparticles (NPs) based thin films were used as active layers in solid state resistive chemical sensors. NPs were synthesized by high temperature solution phase reaction. Sensing NP ...monolayers (ML) were deposited by Langmuir–Blodgett (LB) techniques onto chemoresistive transduction platforms. The sensing ML were UV treated to remove NP insulating capping. Sensors surface was characterized by scanning electron microscopy (SEM). Systematic gas sensing tests in controlled atmosphere were carried out toward NO2, CO, and acetone at different concentrations and working temperatures of the sensing layers. The best sensing performance results were obtained for sensors with higher NPs coverage (10 ML), mainly for NO2 gas showing interesting selectivity toward nitrogen oxides. Electrical properties and conduction mechanisms are discussed.
The work reports on theoretical and nanoscale characterization of Au/Co/Au multilayers used as transducers in Magneto-optical Surface Plasmon Resonance (MOSPR) biosensors. Different aspects related ...to the optimization of transducers are discussed. In particular, optimized sensitivity is demonstrated to depend on the full multilayer total thickness, on the Co layer thickness and its position within the film, as well as on the discrepancy between the optical constants in very thin layers with respect to bulk values. Co layer thickness and position in the trilayer are optimized to provide the best compromise between magneto-optic (MO) activity and optical losses as well as to ensure large electromagnetic (EM) fields at the Au-dielectric interface. In this sense surface sensitivity can be maximized with respect to variations in the bulk properties of the measuring fluid and ensure higher performances with respect to traditional SPR biosensors. In parallel, a comprehensive study on the structural, morphological, chemical, magnetic and optical properties of layers composing the realized magneto-plasmonic (MP) transducers is reported by comparing the results of experimental and theoretical investigations. High resolution TEM (HR-TEM) images provided a deep insight on the interfaces morphologies thus revealing a significant discrepancy between modelled and real samples basically due to sizable roughness at each metal interface. As highlighted by hysteresis loop measurements, this parameter results having a critical role in tailoring the magnetic and consequently magneto-plasmonic properties of the trilayer transducers. As a proof of concept, a simple immunoassay relative to the study of an antibody-antigen interaction in liquid phase has been investigated.
Ethane-bridged Zn porphyrins dimers (ZnPP) have been deposited by Langmuir–Schäfer (LS) deposition technique onto proper transducer layers for surface plasmon resonance (SPR) and magneto-optical ...surface plasmon resonance (MO-SPR) characterization techniques performed in controlled atmosphere. This last tool has emerged as a novel and very performing sensing technique using as transducer layers a combination of noble and magnetic layers deposited onto glass substrates. A magnetic actuation allows recording a magneto optical SPR signal which ensures best gas sensing performances in terms of signal to noise ratio, sensitivity and limit of detection parameters. Primary and secondary amines in vapour phase have been used as sensing analytes and a possible explanation of the mechanism as well as of the dynamics of the interaction with the sensing Zn Porphyrin layers is provided.
Matrix assisted pulsed laser evaporation (MAPLE) is a new promising laser-based technique thought for polymer or biomaterial thin films deposition. In this work, the MAPLE technique has been used for ...the deposition of titania (TiO2) nanoparticle thin films to be used for gas sensor applications. For this purpose, an aqueous solution of TiO2 nanoparticles, synthesized by a novel chemical route, was frozen at the liquid nitrogen temperature and introduced in a vacuum chamber to be irradiated with a pulsed ArF excimer laser. The volatile solvent was pumped away while the TiO2 nanoparticles were deposited on Si and Al2O3 substrates. A uniform distribution of TiO2 nanoparticles with an average size of about 10nm was obtained, as demonstrated by high resolution scanning electron microscopy (SEM-FEG) inspection. We realized gas-sensing devices based on resistive transduction mechanism by using the TiO2 nanoparticles thin films deposited by the MAPLE technique onto suitable rough alumina substrates equipped with interdigitated electrical contacts (IDC) and heating elements. Electrical characterization measurements were carried out in controlled environment. The results of the gas-sensing tests towards low concentrations of ethanol and acetone vapors are reported. Typical gas sensor parameters (gas responses, response/recovery time, sensitivity, and low detection limit) towards ethanol were extracted and compared with to the corresponding parameters towards acetone.
We investigated the fluorescence (FL) dependence on the environment oxygen content of poly(9,9-dioctylfluorene) (PF8) thin films. We show that the PF8 interactions with oxygen are not limited to the ...known irreversible photo-oxidation, resulting in the formation of Keto defects, but also reversible FL quenching is observed. This effect, which is stronger for the Keto defects than for the PF8, has been exploited for the realization of a prototype oxygen sensor based on FL quenching. The sensing sensitivity of Keto defects is comparable with the state of the art organic oxygen sensors based on phosphorescence quenching.
Over the last decades, the social context has been characterized by uncertainty, complexity, and inequalities, with significant impacts on people, groups, and communities. Covid-19 Pandemic has ...accentuated social discriminations, as inequalities affecting women (
World Health Organization, 2018
), with repercussions on general income, health, education (
Office for National Statistics, 2021
) that have been exhausting people, the economic system, and the welfare state (
Antonicelli et al., 2020
). To cope with these difficulties, on april 10, 2020 the Italian Prime Minister appointed a Task Force of 17 experts with scientific and applicative skills in social and economic fields. Within a short time, the Task Force aimed at identifying practical solutions priming the relaunch of the country. Given the women’s central role in the country’s social and economic development, in the final version of the Task Force plan, Gender Equality was indicated as the third—strategic and innovative—axis, together with Digitization and Green Economy. Its rationale was to promote gender equality in every action, with an allocation of dedicated economic resources. Specifically, the Task Force’s Working Group named “Individuals, Families, and Society” proposed specific initiatives aimed at recognizing and bridging the gender gaps in the various areas, and measures to support vulnerable people. This contribution will focus on the central role that the Task Force has played in encouraging systematic attention to women, considering their needs and the social-economic impacts on their choices and well-being. It will illustrate the Task Force’s internal dynamics (there were four women out of 17 people, then increased), the process of inclusion of different perspectives, both gender and multidisciplinary, and the practices suggested for the post-pandemic rebuilding. The final goal will be to show the inability to promote innovation, resilience and sustainability, without working with and for the community. As shown by the Italian Task Force, an innovative change must consider a multiplicity of perspectives that reflects the complexity of reality, even in the political and decision-making debate. Therefore, it’s central to build multidisciplinary teams that include various professionals from the social sectors, as Social Psychology, Sociology, Pedagogy, Political Philosophy, Demography, and Social Statistics, both women and men.
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•Continuous-flow pervaporation is implemented in membrane-microreactors.•As application, ethanol removal from radiopharmaceutical formulations is performed.•The process yield is ...influenced by the membrane surface area/chip volume ratio.•Ethanol is reduced well below 10% v/v as required by the European Pharmacopea.
A pervaporation process was implemented into microfluidic chips to purify radiopharmaceuticals for Positron Emission Tomography in continuos-flow. The chip consists of a serpentine microreactor interfaced to a polydimethylsiloxane (PDMS) 10 μm thick membrane. Thanks to different volatility of the components present in the radiopharmaceutical matrix, ethanol (EtOH) is readily removed under gentle heating and nitrogen flow conditions. Three classes of chips with different membrane surface areas (S) and internal volumes (V) have been produced and quantified their pervaporative efficiency at different residence times (Rt) and temperatures. Higher S/V chips (̴ 70 mm−1) apperared the most efficient at a very low residence time (Rt ̴ 10 s) allowing reduction of 67% at 80 °C. Chips of intermediate S/V ratios (̴ 30 mm−1) decreased the EtOH amount up to ̴ 90% at longer residence time (Rt ≥ 26 s). The halving of EtOH concentration in a solution of a radiotracer was obtained at 50 °C with Rt of 25 s. After the pervaporation treatment, the EtOH content in the final radiopharmaceutical formulation was demonstrated to be reduced below 10% v/v as required by the European Pharmacopea current edition.
Incidental gastrointestinal findings are commonly detected on MDCT exams performed for various medical indications. This review describes the radiological MDCT spectrum of appearances already present ...in the past literature and in today’s experience of several gastrointestinal acute conditions such as abdominal hernia, giant colon diverticulum, GIST, intestinal pneumatosis, colon ischemia, cold intussusception, gallstone ileus, and foreign bodies which can require medical and surgical intervention or clinical follow-up. The clinical presentation of this illness is frequently nonspecific: abdominal pain, distension, nausea, fever, rectal bleeding, vomiting, constipation, or a palpable mass, depending on the disease. A proper differential diagnosis is essential in the assessment of treatment and in this case MDCT exam plays a central rule. We wish that this article will familiarize the radiologist in the diagnosis of this kind of incidental MDCT findings for better orientation of the therapy.
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