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We investigated the temporal concentration of floatable plastic particles in the Po river, the largest contributor of freshwater to the Adriatic Sea. Surface waters were sampled in 2019 with a Manta trawl, with almost bimonthly frequency. In total, 5063 plastic particles were collected, 80.6% of which were microplastics (<5 mm). Characterization through FT-IR spectroscopy evidenced 7 polymers, of which polyethylene, polypropylene and polystyrene accounted for 40.5%, 25.7%, and 14.9%, respectively. The highest plastic concentration was recorded in December (3.47 particles m -3 ; 5.89 mg m -3 ), while the lowest in August (0.29 ± 0.01 particles m -3 ; 0.22 ± 0.08 mg m -3 ). We estimated the annual load of floatable plastic particles carried by the Po river to be 145 tons. Plastic particle load was correlated with the hydraulic regime, and was higher in autumn and spring months., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This is the first survey to investigate microplastic contamination in the Northern Tyrrhenian seafloor, along a 31 km-long transect from the port of Piombino (Tuscany) to the port of Portoferraio (Elba Island). Plastics extracted from 58 sediment samples were counted and identified by Fourier-transform infrared spectroscopy (FTIR). Plastic pollution occurred in sites closer to ports as well as in offshore stations. Microplastics (1-5 mm) accounted for over 80% of particles. For all samples, the dominant microplastic type was filaments, followed by fragments and films. Six polymers were identified: nylon, polyurethane, polyethylene, and polyethylene terephtalate were the most common. This part of the Tyrrhenian Sea is a busy shipping route connecting the mainland to the Elba Island, with thousands cargo and passenger ships passing by per year. Our data constitute a baseline for microplastic research in the Tyrrhenian seafloor., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This is the first survey to investigate the occurrence and extent of microplastic contamination in sediments collected along a coast-open sea 140km-long transect in the Central Adriatic Sea. Plastic debris extracted from 64 samples of sediments were counted, weighted and identified by Fourier-transform infrared spectroscopy (FT-IR). Several types of plastic particles were observed in 100% of the stations. Plastic particles ranged from 1 to 30mm in length. The primary shape types by number were filaments (69.3%), followed by fragments (16.4%), and film (14.3%). Microplastics (1-5mm) accounted for 65.1% of debris, mesoplastics (5-20mm) made up 30.3% of total amount, while macro debris (>20mm) accounted for 4.6% of total plastics collected. Identification through FT-IR spectroscopy evidenced the presence of 6 polymer types: the majority of plastic debris were nylon, polyethylene and ethylene vinyl alcohol copolymer. Our data are a baseline for microplastic research in the Adriatic Sea., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This is the first survey to investigate the occurrence and extent of plastic contamination in sediments collected in Terra Nova Bay (Ross Sea, Antarctica). Plastic debris extracted from 31 samples of sediments were counted, weighted and identified by Fourier-transform infrared spectroscopy (FT-IR). All sediment samples contained plastics: a total of 1661 items of debris (3.14g) were recorded from the 31 samples of sediment. Plastic particles in the samples ranged from 0.3 to 22mm in length. Fibres were the most frequent type of small plastics debris detected. In terms of abundance, microplastics (<5mm) accounted for 78.4% of debris. 9 polymer types were found: the most common material (94.13% by weight) was styrene-butadiene-styrene copolymer (SBS), widely used in pneumatic tires, etc. A decreasing concentration of plastic debris at increasing distances from the Mario Zucchelli Base was evidenced., (Copyright © 2017. Published by Elsevier Ltd.)

Small plastic debris in sediments from five beaches were investigated to evaluate their occurrence and abundance in the Northern Adriatic coast for the first time. Plastic debris extracted from sediments were counted, weighted and identified by Fourier-transform infrared spectroscopy (FT-IR). A total of 1345 items of debris (13.491g) were recorded, with a mean density of 12.1 items kg -1 d.w. and 0.12gkg -1 d.w. Fragments were the most frequent type of small plastics debris detected. In terms of abundance, microplastics (<5mm) accounted for 61% of debris, showing their wide distribution on Adriatic coasts, even far-away from densely populated areas. The majority of the polymers found were polyolefins: there were greater quantities of polyethylene and polypropylene compared to other types of plastic. Primary microplastics accounted for only 5.6% of the total plastic debris. There were greater quantities of microplastics at sites subjected to stronger riverine runoff. The results will provide useful background information for further investigations to understand the sink and sources of this emergent and priority contaminant., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

We present the first type of tetraazide-functionalized calix[4]arene TiO(2) nanoparticles and their coupling to propargyl glycosides under Cu(I)-catalysis (click reaction), resulting in the immobilization of calix[4]arene-based glycoclusters on the TiO(2) surface.

In this work we study the effects of the optical shrinkage in polymer and liquid crystal (LC) mixtures optimized for their use as active media in compact plastic laser devices. These mixtures are characterized by the presence of the rhodamine 6G as an active dye. Modifications in the reflection properties of the gratings as a function of the active dye concentration have been determined experimentally and a detailed theoretical simulation of the optical transmittance properties of these devices is provided. Moreover, the comparison between two different experimental approaches clarifies the contribution to the optical shrinkage due to the presence of the active dye. In principle this approach allows determining the linear mechanical shrinkage by separating the contribution to optical shrinkage due to photochemical transformations from that due to mechanical effects.

The aim of this study was to evaluate polyurethane percutaneous endoscopic gastrostomy (PEG) tube degradation and the role played by fungi. The inner surfaces of 20 used polyurethane tubes were brushed, and the brushing end was incubated for 7 days in Saburaud broth and cultured if fungal growth occurred. Three tubes used for 12 (sample 12w), 17 (sample 17w), and 96 (sample 96w) weeks and two new tubes were cut to produce several 4-cm-long equal halves. Six samples from the new tubes were considered control samples (Co sample), seven were incubated in Saburaud broth (Co sample + Sa.), and seven in the broth supplemented with Candida albicans (Co sample + Sa. + Ca). All samples underwent morphological examination by electron microscopy and differential scanning calorimetry measurements (DSC). All tubes had fungal colonization. DSC showed deterioration in all tubes including the new ones; adding Candida albicans had no additional effects. Morphological examination by electron microscopy showed a regular pattern in the Co sample, and thick biofilm, holes, and crevices in samples 12w, 17w, and 96w. The more the tubes had been used, the more severe were the changes. The Co sample + Sa and the Co sample + Sa + Ca showed no changes in the inner surface, but cryogenically fractured surfaces had holes and crevices. Yeasts constantly colonize PEG tubes and are likely to contribute to polyurethane deterioration. The impairment of new PEG tubes incubated in Saburaud broth suggests that other factors also play a role in polyurethane deterioration.

The brainstem-evoked response audiometry (BERA) is probably the most common approach to hearing assessment in high-risk and developmentally handicapped infants. It is usually suggested, however, that BERA should not be the sole assessment method. In an attempt to determine an effective supplement to BERA, the present study evaluated a classical conditioning procedure with developmentally impaired babies. Within this procedure, different tones served as conditioned stimuli while an air-puff was used as the unconditioned stimulus. Results indicate that this procedure could be successfully applied with almost all of the babies.