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• The massive production of plastic material currently represents one of the major environmental problems that requires the development of efficient and cost-effective recycling processes. • The degradation of end-of-life plastics using microorganisms or enzymes is a promising strategy, which can lead to the obtainment of monomers with high added value. • Appropriate pretreatments on the starting plastic material can modify the properties of the polymer and make it more susceptible to biodegradation or enzymatic degradation. In recent years, enzymatic degradation and biodegradation have attracted great interest in the recycling of plastic waste. Compared to other recycling techniques, they have numerous advantages such as mild reaction conditions both in terms of temperature and pressure and the prevention in the use of toxic solvents. The monomers formed during the degradation processes can result in chemicals with high added value, which can be purified and reused at an industrial level. Unfortunately, numerous factors, both environmental and related to polymer's nature, influence enzymatic degradation and biodegradation, making them very complex processes. An effective way to increase degradation consists in subjecting the plastic material to pretreatments of various kinds, capable of inducing modifications in the polymer and making it more susceptible to the action of microorganisms or enzymes. This review has the objective of analyzing the literature of the last 15 years, to identify the most efficient pretreatments on the base of the polymer's chemistry, also considering technical-economic aspects. [ABSTRACT FROM AUTHOR]

Hypothesis In a saturated cement paste, there are three different types of water: the structural water chemically reacted with cement, the constrained water absorbed to the surface of the pores, and the free water in the center of the pores. Each type has different physicochemical state and unique relation to cement porosity. The different water types have different dynamics which can be detected using quasi-elastic neutron scattering (QENS). Since the porosity of a hardened cement paste is impacted strongly by the water to cement ratio ( w / c ), it should be possible to extract the hydration dependence of the pores by exploiting the dynamical parameters of the confined water. Experiments Three C–S–H samples with different water levels, 8%, 17% and 30% were measured using QENS. The measurements were carried out in the scattering vector, Q , range from 0.5 Å −1 to 1.3 Å −1 , and in the temperature interval from 230 K to 280 K. The data were analyzed using a novel global model developed for cement QENS spectra. Findings The results show that while increasing the water content, the structural water index ( SWI ) decreases and the confining radius, a , increases. Both SWI and a have a linear relationship with the water content. The Arrhenius plot of the translational relaxation time shows that the constrained water dominates the non-structural water at water contents lower than 17%. The rotational activation energy is smaller for lower water content. The analysis demonstrated that our newly proposed global model is practical and useful for analyzing cement QENS data. [ABSTRACT FROM AUTHOR]

Chia seed mucilage represents an emerging resource in food industry due to its particular tetrasaccharide (repeating unit) composition. In this investigation, we report on the effect of biomacromolecule concentration and ageing on the structural integrity of chia mucilage-based hydrogel networks. Hydrogels were produced with different polymer concentration and analyzed as prepared and after 10 days of ageing. Structural studies were undertaken through scanning electron microscopy, rheology and small angle X-ray scattering (SAXS). Rheological characterization revealed that ageing acts as destabilizing factor for hydrogel architecture. Indeed, hydrogel strength as well as viscosity were found to decrease upon ageing. This behavior related with a structural change was validated by microscopy. Strikingly, the formation of less entangled and packed meshwork was evidenced. SAXS elucidated that the mesh size of the hydrogel network increased with ageing. Overall, the ageing information provided in this study has to be taken into account when using chia mucilage as a food ingredient or in other application fields. [Display omitted] • Formation of less entangled and packed meshwork was evidenced. • Ageing acts as destabilizing factor for hydrogel architecture. • Mesh size of the hydrogel network increased with ageing. [ABSTRACT FROM AUTHOR]

Abstract: Using incoherent quasi-elastic and inelastic neutron scattering, we have investigated the hydrogen relaxational dynamics and hydrogen vibrational modes in the polyoxomolybdate specie [Mo72Fe30O252(CH3COO)12[Mo2O7(H2O)]2[H2Mo2O8(H2O)](H2O)91]·≈150 H2O. The translational dynamics of the water molecules in the compound is profoundly different from that of bulk water at the same temperature showing a non-Debye relaxation behavior. The temperature dependence of the relaxation time can be described in terms of an Arrhenius law, indicating that the dynamics is triggered by the breaking of the bonds connecting the crystal water molecules with the hydrophilic nanocapsule surfaces. Inelastic neutron scattering spectra confirm the attenuation of water translational modes with respect to the bulk water case due to the strong destructuring effect imposed by the nanocage interface and the enhancement of the highest frequency librational mode as already found in hydrated Vycor or Gelsil matrix. Small angle X-ray scattering on freshly prepared aqueous solution evidences the presence of nanocapsule structures proper of the monomer (2.6nm in diameter) that coexist with a small amount of oligomers. After 1month the polyoxomolibdate specie self-assembles in a supramolecular structure with a polydisperse distribution of dimensions spanning from the monomer to the “blackberry” vesicular structure already reported in literature. [ABSTRACT FROM AUTHOR]

Abstract: Spermine oxidase (SMO) is a FAD-containing enzyme involved in animal cell polyamines (PA) homeostasis, selectively active on spermine and producing H2O2, spermidine, and the 3-aminopropanal. In the present study, we have examined the SMO gene expression during the mouse myoblast C2C12 cell differentiation induced with two different stimuli by RT-PCR analysis, polysome-mRNP distribution and enzyme activity. SMO transcript accumulation and enzymatic activity increases during C2C12 cell differentiation and correlates with the decrease of spermine content. Many proteins are highly regulated during the phenotypic conversion of rapidly dividing C2C12 myoblasts into fully differentiated post-mitotic myotubes. The SMO gene induction represents a novel and additional marker of C2C12 cell differentiation. The sub-cellular localization of the SMOα and SMOμ splice variants is not involved in the differentiation processes. Nuclear localization of only the SMOμ protein was confirmed. [Copyright &y& Elsevier]

Abstract: Nanoparticles consisting of a magnetic core (γ-Fe2O3) and an organic shell were prepared by thermal decomposition of an iron carbonyl complex in the presence of oleic acid. The nanoparticles were then dispersed in cyclohexane to form a stable ferrofluid. These dispersions were investigated by means of Small Angle Scattering of X-rays (SAXS) and the data were interpreted according to a “pearl necklace” model, opportunely modified to account for the core-shell structure of the magnetic nanoparticles. The results of the fittings show that nearly monodisperse spherical particles with a radius of the magnetic core of about 3.9 nm and a shell of about 2 nm were obtained. These nanoparticles self-assemble in chain-like structures, even in the absence of an applied magnetic field. [Copyright &y& Elsevier]

In this work, we proposed the use of differential scanning calorimetry (DSC) as a rapid tool for the discrimination of meat samples coming from free-ranged and caged rabbits. Fatty acid composition, colour, and texture were also provided to fully characterize meat quality of the different samples. A total of 36, thirty-seven days old California × New Zealand White male rabbits were divided into 2 groups, housed in open air cages and in ground free-range, respectively. After 62 days of farming, 12 rabbits per group were slaughtered and the skinned carcasses were chilled for 24 h at 4 °C prior to be dissected. The Longissimus thoracis et lumborum muscle was analysed. The overall fatty acid profile was not affected by the farming system, while free-range rabbits show a significant lower L* value (49.59) than the open-air ones (53.54). Nor a* and b* were altered. Texture measurements revealed that there was no effect of housing system on shear force. More interestingly, the deconvolution of DSC signals in the range 30–90 °C revealed that free-range rearing lead to an increase of myosin amount in meat, being its peak percentage equal to 8.5 ± 1.9 against 4.3 ± 2.2 in meat from caged rabbits. • Meat from free-ranged and caged rabbit meat was discriminated thanks to DSC. • An increase of myosin amount in meat from free-ranged rabbit was observed. • Meat lightness was affected by rearing conditions. • Texture and fatty acid profile scarcely differentiate between farming systems. [ABSTRACT FROM AUTHOR]

A method to prepare solvent free castor oil (CO) based polyurethane (PU) adhesives with different ratios of CO and hexamethylene diisocyanate (HMDI) has been developed and the relationships between the microstructure and mechanical properties investigated. Solvent free castor oil-based PU adhesives were synthesized by promoting the reaction between castor oil and HMDI, at room conditions, and by varying the CO/HMDI weight ratio in the range 1:0.032–1:0.32 wt%. The curing of these adhesives did not require any external stimuli such as heat or irradiation treatment and once cured at room temperature they were stable up to 140 °C and water-resistant. A multi-technique approach was used to characterize so-obtained adhesives. The adhesion energy in metal–metal contact was evaluated as a function of the debonding velocity ( V d ) through tack experiments. The mechanical properties were influenced by the NCO/ OH ratio, which varies the crosslinking density in the adhesives. Moreover, the structure–mechanical property relationship was explored and the inter-correlation between the storage modulus ( G’ ), adhesion energy ( E ad ) and correlation length ( ξ ) detailed, with both G’ , E ad increasing while ξ decreased. These solvent-free bio-based adhesives showed capability to adhere different substrates such as wood, paper, textile, and metal, which makes them promising candidates in different industrial and commercial applications. [ABSTRACT FROM AUTHOR]

Abstract: Acetic and formic acid vapors emitted from woodwork in historical organs are very important corrosive agents for lead pipes. These acids are slowly released from the wood both during playing and when the pipes are silent. To inhibit this emission process, the wood surface can be modified, by creating a protective layer with alkaline features. However, a coating of wood is not recommended since this could modify the appearance and create a layer not perfectly compatible with the substrate. For this reason, we propose to use some innovative nanotechnology that has been successfully applied for the deacidification of wood samples coming from the Vasa shipwreck. Application of calcium (or magnesium) hydroxide nanoparticles, with sizes ranging from 30–150nm, allowed a homogeneous distribution of particles through the surface layer of wood simply by soaking (or spraying) it in a alcoholic (or mixed with less polar solvents) dispersion of nanoparticles. Nanoparticles do not modify the wood appearance and distribute randomly within the first layers of wood. The small size of particles accounts for the high reactivity with CO2 from the air, to give the alkaline reserve of carbonates that provide high efficacy in the neutralization of gaseous acids. The emission of volatile organic compounds (VOC) from the treated wood was determined by using an emission test cell, Field and Laboratory Emission Cell (FLEC). The results show that the emissions of acetic acid vapor from nanoparticles treated wood was very low (<70μg/m2 h) during the first 13 month. In contrast, untreated wood emitted high concentrations of acetic acid vapor (200–400μg/m2 h). [Copyright &y& Elsevier]

In this work, a low-cost, disposable, and portable lab-on-paper device is proposed to simultaneously quantify total polyphenol content (TPC) and antioxidant capacity (AOC) in 15 min; the assay requires no pre-treatment of the samples. The lab-on-paper device fabrication has been carried out employing a xurography-based benchtop microfabrication technology using low-cost materials as chromatography paper and polymeric sheets. Extra virgin olive oil (EVOO) phenolic compounds' represents a nutritional added value, nevertheless, the high lipidic content hinders their direct and rapid analysis, resulting in an extremely challenging sample. The realized lab-on-paper allows to perform the dual TPC and AOC determination in three simple steps: (i) sample loading, (ii) analytes transport to the analysis spot, and (iii) double colorimetric analysis exploiting the growth of AuNPs and AgNPs on paper mediated by phenolic compounds. Signal acquisition is achieved using a standard digital camera. The dual colorimetric assay is able to detect phenolic compounds in the 25–500 mg L−1 range with limits of detection ≤6 mg L−1 and good reproducibility (RSDs ≤11%). Direct analysis of EVOO samples (n = 30) correlated well (r > 0.92) with conventional spectrophotometric methods for TPC and AOC determination. [Display omitted] • A dual read-out colorimetric lab-on-a-paper device has been fabricated. • Benchtop technologies and office-grade sources were used to produce the device. • The device allows direct simultaneous phenols and antioxidant capacity analysis. • The device allowed reliable extraction-free analysis of 30 olive oil samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hypothesis: phenolic compounds-capped AgNPs exhibit different antifungal activity. • Stable AgNPs were synthesized using different pure phenolic compounds (PCs). • Di-hydroxylic and tri-hydroxylic phenolic acids and flavonoids were used. • AgNPs@PCs exhibited different growth inhibition activity against Aspergillus niger. • In the same conditions/dimensions, PCs' structure modulate AgNPs antifungal capacity. An exponential increase of scientific works dealing with the use of polyphenol-rich 'natural products' for the synthesis of bioactive AgNPs is in progress. However, a lack of fundamental studies on phytochemical compounds involved, and their role is evident. In this work, a comprehensive study of the antifungal performances of silver nanoparticles (AgNPs) synthesized exclusively with phenolic compounds (PCs) with different structures and different antioxidant capacity is presented. The experimental hypothesis is that AgNPs@PCs produced with different PCs can exert different toxicity. In particular, di-hydroxylic and tri-hydroxylic phenolic acids (caffeic acid and gallic acid) and flavonoids (catechin and myricetin) were compared. A room temperature rapid and simple AgNPs synthesis was carefully optimized, obtaining stable and reproducible colloids. AgNPs@PCs suspensions were characterized by UV–vis spectroscopy, ς-potential, dynamic light scattering and transmission electron microscopy. AgNPs@PCs radical scavenging capacity was also assessed. Finally, the AgNPs@PCs antifungal effect was tested against Aspergillus niger , particularly on spore germination and mycelial growth. The different antifungal activity was attributed to the different PCs' ability to generate/stabilize AgNPs with different shells, residual antioxidant capacity, and capacity to interact and aggregate during their 'attack' to A. niger hyphae. This work paves the way for the rational use of PCs and PCs rich-products for AgNPs-based applications. [ABSTRACT FROM AUTHOR]

Blister beetles owe their name to their ability to release cantharidin, a blistering terpene, the highest concentration of which is retained in male accessory glands. The anatomy and ultrastructure of the three pairs of male reproductive accessory glands and the glandular region of the two vasa deferentia of Meloe proscarabaeus were investigated using light, electron and ion beam microscopy. All of the mesodermal glands here analysed share a common structural organization with an outer muscular layer and an inner glandular epithelium facing a broad lumen in which the secretory products are released. Developed rough endoplasmic reticulum, Golgi systems, abundant mitochondria, numerous secretory vesicles and a microvillated apical membrane are commonly found in the cells of different glandular epithelia, suggesting that all accessory gland pairs as well as the vasa deferentia are involved in an active synthesis. Nevertheless, each pair of glands appears specialized in the production of a specific set of substances, as suggested by the peculiarities in cellular ultrastructure and by the different aspect of the secretions stored in their glandular lumen. The above cited features of male accessory glands of M. proscarabaeus are compared with those of other beetles and some hints on their potential role in producing and/or concentrating cantharidin are provided. Image 1 • Male accessory gland ultrastructure is analysed for the first time in Meloidae. • All the reproductive male accessory glands are of mesodermic derivation. • We assess the glandular function of the vasa deferentia in Meloe proscarabaeus. • Different pairs of glands show specific ultrastructural features and secretions. • Cells of the third accessory gland pair have a convoluted basal lacunar system. [ABSTRACT FROM AUTHOR]