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The incorporation of silica nanoparticles (Si-NPs) into the polymer matrix is a growing area of interest research to produce high-performance polymer nanocomposites (NCs) across a wide range of nanotechnology applications. This improvement is due to the Si-NPs capability to self-assembly giving rise to specific well-organized structures with both short- and long-range order across a hierarchy of spatial scales, determined by both NP-NP and NP-matrix interactions, involving a careful balance among attractive driving forces, repulsive forces, and directional forces. Respect to this, the aim of the present paper is to systematically review the use of Si-NPs in polymer NCs and on the role of NPs self-assembly in determining the final material properties. Firstly, we explored the synthesis and modification of both isotropic and anisotropic Si-NPs in relation with use in NC materials, focusing on NPs dispersion and distribution, as well as on the functionalization strategies of Si-NPs. Besides Si-NPs functionalization with conventional small organic molecules, a large section is devoted to an emerging class of functionalized Si-NPs with macromolecules, namely silica hairy NPs (Si-HNPs), able to give rise a rich variety of complex assemblies and materials with new structures and functionalities. Successively, NCs materials containing Si-NPs and Si-HNPs have been explored in terms of synthetic preparation and properties. The self-organization of Si-NPs and Si-HNPs in polymer matrices has been reported and its effect on the functional materials properties have been evaluated with a critical point of view on the results, limits, and future perspectives. Our review can be considered a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology and nanoscience, taking into consideration the fundamental role of NPs self-assembly processes in determining the functional material properties.

Inorganic nanostructured (metal) oxides are a large class of inorganic materials extensively investigated for their unique and outstanding properties that allow for their use within a multitude of technological fields of emerging interest, such as (photo)catalysis, environmental remediation processes, energy storage, controlled transport and/or release of drugs and chemicals, biomedicine, sensing, development of smart materials, stimuli-responsive materials, and nanocomposites [...]

Even if cement is a well-consolidated material, the chemistry of cement (and the chemistry inside cement) remains very complex and still non-obvious. What is sure is that the hydration mechanism plays a pivotal role in the development of cements with specific final chemical compositions, mechanical properties, and porosities. This document provides a survey of the chemistry behind such inorganic material. The text has been organized into five parts describing: (i) the manufacture process of Portland cement, (ii) the chemical composition and hydration reactions involving a Portland cement, (iii) the mechanisms of setting, (iv) the classification of the different types of porosities available in a cement, with particular attention given to the role of water in driving the formation of pores, and (v) the recent findings on the use of recycled waste materials in cementitious matrices, with a particular focus on the sustainable development of cementitious formulations. From this study, the influence of water on the main relevant chemical transformations occurring in cement clearly emerged, with the formation of specific intermediates/products that might affect the final chemical composition of cements. Within the text, a clear distinction between setting and hardening has been provided. The physical/structural role of water in influencing the porosities in cements has been analyzed, making a correlation between types of bound water and porosities. Lastly, some considerations on the recent trends in the sustainable reuse of waste materials to form “green” cementitious composites has been discussed and future considerations proposed.

Waste management is a most current topic, and as such, numerous articles in literature discuss over the recycling and re-use of waste materials from various fields. A common solution is the to use these materials as partial substituent of the inert fraction in concretes and mortars. This work focuses on the possibility of using Acanthocardia tuberculata seashells, which constitute a food waste destined to landfilling, as partial substituents of inert in mortars. The results obtained evidenced that the reduction in mechanical properties (in terms of toughness and flexural stress) is mainly due to the water absorption properties of seashells aggregates, which affect the hydration of the cement. However, as experimentally demonstrated, such decrease in mechanical properties in any case does not compromise the performance of the material when used for civil applications. Resumen: La gestión de residuos es un tema actual, y como tal, numerosos artículos en la literatura discuten sobre el reciclaje y la reutilización de materiales de desecho de diversos campos. Una solución común es utilizar estos materiales como sustituyentes parciales de la fracción inerte en hormigones y morteros. Este trabajo se enfoca en el posible uso de conchas marinas Acanthocardia tuberculata, que constituyen un desperdicio de alimentos destinados al relleno sanitario, como sustituyente parcial del inerte del mortero. Los resultados obtenidos evidenciaron que la reducción de las propiedades mecánicas (en términos de tenacidad y resistencia a flexión) se debe principalmente a las propiedades de absorción de agua de las conchas marinas, que afectan la hidratación del cemento. Sin embargo, como se demostró experimentalmente, dicha disminución de las propiedades mecánicas en cualquier caso no compromete el rendimiento del material cuando viene empleado en aplicaciones civiles.

espanolThe continuous research of new functional materials combining both advanced properties and increased sustainability has dramatically risen up in the last decades. Instead of searching for new solutions, composites (formed by a combination of already present materials) are subject of different studies due to their capability of merging the advantages of components. Hence, chitosan, a biowaste-derived biopolymer, has been thermally-converted into chars by pyrolysis treatment. Subsequently, both chitosan and its char are introduced into cementitious matrix forming cement-based composites. The analysis of the mechanical properties of these materials evidenced that char-containing composites show an incipient fracture toughness capability, very appealing for possible structural applications. EnglishLa investigacion continua de nuevos materiales funcionales que combinan propiedades avanzadas y una mayor sostenibilidad ha aumentado dramaticamente en las ultimas decadas. En lugar de buscar nuevas soluciones, los compuestos (formados por una combinacion de materiales ya presentes) estan sujetos a diferentes estudios debido a su capacidad de fusionar las ventajas de los dos componentes. El quitosano, un biopolimero derivado de residuos biologicos, se ha convertido termicamente en carbon mediante tratamiento de pirolisis. Posteriormente, tanto el quitosano como su carbon se introducen en una matriz cementosa que forma compuestos a base de cemento. El analisis de las propiedades mecanicas de estos materiales puso de manifiesto que los compuestos que contienen carbon muestran una incipiente capacidad de resistencia a la fractura, muy atractiva para posibles aplicaciones estructurales.

The continuous growing demand of fresh water to fulfil agricultural, industrial, and domestic needs of the global population points out the technological importance of performing smart and efficient wastewater remediation processes. One of the major problems related to water quality is represented by the impact due to emerging pollutants (EPs), a wide class of anthropic chemicals recently recognized (but poorly regulated), hardly removable by traditional treatments.[1] Hence, innovative heterogeneous processes based on the application of hybrid inorganic-organic magnet-responsive nanomaterials (MRNs, e.g., magnetic iron oxides) are receiving great attention as interesting alternative technologies exploitable in light-enhanced advanced oxidation processes (AOPs), and in more traditional sorption routes.[2] In this study, MRNs are functionalized by means of two different bio-based macromolecules, namely: BBS (i.e., humic-like substances isolated from green compost derived from agricultural biowaste), and chitosan (i.e., an amino-polysaccharide derived from shellfish industry biowaste). Both these organic macromolecules are in line with the “Waste Cleaning Waste” approach, very appealing from the green chemistry viewpoint.[3] Eventually, it has been investigated the possibility of converting such organic fractions into carbonaceous phases via pyrolysis, still maintaining the magnetic properties of the inorganic component. Hybrids MRNs are physicochemical, magnetic, and morphological characterized. Finally, in view of showing the potentiality of these hybrid systems, several case studies are discussed, in details: i) Testing BBS-iron oxide systems against caffeine (taken as model EPs) via light-enhanced AOPs at circumneutral conditions.[1] ii) Testing chitosan-derived carbonaceous-iron oxide systems against anthracene and naphthalene via sorption mechanism.[4] iii) Testing all hybrid systems against As(III) and As(V) via sorption mechanism.[5] Results indicate that these hybrid MRNs are a promising technological solution for the new generations of wastewater purification treatments. Acknowledgements: European Commission H2020-MSCA-RISE-2014, research project Mat4treaT (Project 645551). [1] F. Franzoso, R. Nisticò, F. Cesano, I. Corazzari, F. Turci, D. Scarano, A. Bianco Prevot, G. Magnacca, L. Carlos, D.O. Martire, Chemical Engineering Journal 2017, 310, 307-316. [2] R. Nisticò, Research on Chemical Intermediates 2017, 43, 6911-6949. [3] P. Avetta, F. Bella, A. Bianco Prevot, E. Laurenti, E. Montoneri, A. Arques, L. Carlos, ACS Sustainable Chemistry and Engineering 2013, 1, 1545-1550. [4] R. Nisticò, F. Franzoso, F. Cesano, D. Scarano, G. Magnacca, M.E. Parolo, L. Carlos, ACS Sustainable Chemistry and Engineering 2017, 5, 793-801. [5] R. Nisticò, L.R. Celi, A. Bianco Prevot, L. Carlos, G. Magnacca, E. Zanzo, M. Martin, Journal of Hazardous Materials 2018, 342, 260-269.

The occurrence of uncontrolled electrostatic discharge (ESD) is among the major causes of damage in unprotected electronic components during industrial processes. To counteract this undesired phenomenon, ESD composites showing static-dissipative and antistatic responses are developed. In particular, static-dissipative materials are able to slow down the flow of electric charges, whereas antistatic materials directly suppress the initial charges induced by undesired charging by properly dispersing conductive fillers within an insulant matrix and thus forming a conductive filler network. In this context, the purpose of this review is to provide a useful resume of the main fundamentals of the technology necessary for facing electrostatic charging. The formation mechanisms of electrostatic charges at the material surface were described, providing a classification of ESD composites and useful characterization methods. Furthermore, we reported a deep analysis of the role of conductive fillers in the formation of filler networks to allow electric charge movements, along with an overview of the different classes of inorganic conductive fillers exploitable in ESD composites, evidencing pros/cons and criticalities of each category of inorganic fillers.

In recent years, a great interest has arisen around the integration of naturally occurring clays into a plethora of advanced technological applications, quite far from the typical fabrication of traditional ceramics. This “second (technological) life” of clays into fields of emerging interest is mainly due to clays’ peculiar properties, in particular their ability to exchange (capture) ions, their layered structure, surface area and reactivity, and their biocompatibility. Since the maximization of clay performances/exploitations passes through the comprehension of the mechanisms involved, this review aims at providing a useful text that analyzes the main goals reached by clays in different fields coupled with the analysis of the structure-property correlations. After providing an introduction mainly focused on the economic analysis of clays global trading, clays are classified basing on their structural/chemical composition. The main relevant physicochemical properties are discussed (particular attention has been dedicated to the influence of interlayer composition on clay properties). Lastly, a deep analysis of the main relevant nonconventional applications of clays is presented. Several case studies describing the use of clays in biomedicine, environmental remediation, membrane technology, additive manufacturing, and sol-gel processes are presented, and results critically discussed.

The lack of robust and low-cost sorbent materials still represents a formidable technological barrier for long-term storage of (renewable) thermal energy and more generally for Adsorptive Heat Transformations—AHT. In this work, we introduce a novel approach for synthesizing cement-based composite sorbent materials. In fact, considering the number of available hygrosopic salts that can be accommodated into a cementitious matrix—whose morphological properties can be also fine-tuned—the new proposed in situ synthesis paves the way to the generation of an entire new class of possible sorbents for AHT. Here, solely focusing on magnesium sulfate in a class G cement matrix, we show preliminary morphological, mechanical and calorimetric characterization of sub-optimal material samples. Our analysis enables us to theoretically estimate one of the most important figures of merit for the considered applications, namely the energy density which was found to range within 0.088–0.2 GJ/m3 (for the best tested sample) under reasonable operating conditions for space heating applications and temperate climate. The above estimates are found to be lower than other composite materials in the literature. Nonetheless, although no special material optimization has been implemented, our samples already compare favourably with most of the known materials in terms of specific cost of stored energy. Finally, an interesting aspect is found in the ageing tests under water sorption-desorption cycling, where a negligible variation in the adsorption capability is demonstrated after over one-hundred cycles.

This Special Issue, consisting of four reviews and three research articles, presents some of the recent advances and future perspectives in the field of magnetic materials and systems, which are designed to meet some of our current challenges.

The diagnosis of Alzheimer's disease (AD) relies on the presence of amyloidosis and tauopathy, as reflected in cerebrospinal fluid (CSF), independently from the clinical stage. Recently, CSF d-serine has been proposed as a possible new AD biomarker, reflecting dysfunctional activation of neuronal glutamatergic N-methyl-d-aspartate receptor (NMDAR). In this study, we measured blood serum and CSF concentration of two NMDAR modulators, such as d-serine and d-aspartate, in a cohort of drug-free subjects encompassing the whole AD clinical spectrum. In addition, we also analyzed d-serine levels in a cohort of post-mortem AD and control cortex samples. We reported unaltered serum and CSF concentrations of d-serine and d-aspartate in AD patients both during the AD progression and compared to non-demented controls. Accordingly, no correlation was detected between serum or CSF d-serine content and mini-mental state examination or Clinical Dementia Rating. Similarly, cortical d-serine levels were also unaltered in post-mortem samples of AD patients. Overall, our results failed to confirm previous findings indicating the CSF d-serine as a novel biomarker for AD.

Polyethylene terephthalate (PET) is the third most widely diffused polymer exploited in the packaging industry, monopolizing the bottles market for beverages, and covering almost the 16% of the European plastic consumption in the packaging industry. Even if PET primarily derived from fossil sources and remains not-biodegradable in the environment, novel advancements in the field pointed out the possibility of producing PET in a more sustainable way (e.g., from biomasses) or the possibility of biodegrade this polyester through the enzymatic action of specific genetically-modified/isolated bacteria/enzymes. By considering also the high recyclability of PET, and the possibility of potentially indefinitely re-use this material, one can assume that the future of PET is still to be written. Therefore, all aspects involving the industrial production (with traditional and sustainable chemical routes), intrinsic physicochemical/thermal/mechanical properties, undesired degradation phenomena, chemical/mechanical recycling processes, and processability of PET are here critically discussed. A particular emphasis has been dedicated to the role of PET in the packaging industry. The main achievements in the PET processing for food packaging are presented, analyzing advantages and disadvantages of each technology. This document aims at providing a useful instrument that collects past, present, and future of the PET: a well-consolidated material that has been able to renew itself over time.

Even if the carbon nanotubes (CNTs) and their derivatives are commonly used as reinforcing phase in composite materials, also in commercial products, their tendency to agglomerate generally determines a scarce dispersion, thus not maximizing the effect due to the second phase. In this article, a perfect dispersion of highly entangled nanotubes was achieved by using a very simple approach: exploiting the dispersing effect of a low-cost polymer, polyvinyl butyral (PVB), coupled with standard ultrasound sonication. Several dispersion approaches were tested in order to develop a consistent and widely applicable dispersion protocol. The tape casting technology was subsequently used to produce 100 to 300 μm thick PVB-matrix composite tapes, reinforced by multiwall CNTs dispersed according to the optimized protocol. Their mechanical properties were evaluated, and a simple model was used to demonstrate that the effective dispersion of CNTs is the key to obtain significantly improved properties.

In line with the Green Supply Chain Management, Sustainable Supply Chain Management and Natural-Resource-Based Views (NRBV), the present study is as further step of a long range research program initiated in 2004. The project aims to demonstrate municipal bio-waste (MBW) as feedstock to produce bio based chemicals alternative to fossil sourced products. Previous work demonstrated MBW as source of polymeric biosurfactants (BPS) with multiple properties for use in chemical and agriculture sectors. The present paper reports now a new BPS feature, i.e. that BPS are efficient active principles for soil remediation. The study involves three BPS obtained by alkaline hydrolysis from different streams of an MBW treatment plant: the anaerobic digestate of food kitchen waste (FORSUD), the compost (CV) of gardening residues and the compost (CVDF) of a mix of gardening residues, digestate and sewage sludge. The BPS have 5 to over 750 kg/mol molecular weight, characterized by the presence of aliphatic C chains substituted by aromatic moieties and several different acid and basic functional groups. They were used at 0.1–100 g L−1 in aqueous solution to wash soil sampled from an Italian metal polluted site. Collected data statistical analysis was carried out by ANOVA. The recovered washing solutions were analyzed for Cu, Cr, Ni, Zn, Pb. The 50–100 g/L CVDF BPS solutions exhibited 98-81% extraction efficiency, compared to 70-60% for CV and FORSUD. Compared to conventional commercial extractants, CVDF BPS extraction efficiency ranked as CVDF = diethylene triamine pentaacetic acid > ethylene diamine tetraacetic acid > sodium dodecyl sulphate. A new two steps process was studied: (1) use of BPS solution for washing the polluted soil; (2) treating the recovered solution by acidification and membrane filtration to separate a pollutant concentrate from water for further use. Results indicate membrane filtration more efficient and/or sustainable. They confirm BPS as value added products upgrading MBW from societal cost to source of benefits.

Magnetically driven nanosponges with potential application as targeted drug delivery systems were prepared via the addition of magnetite nanoparticles to the synthesis of cyclodextrin and maltodextrin polymers crosslinked with 1,1′-carbonyldiimidazole. The magnetic nanoparticles were obtained separately via a coprecipitation mechanism involving inorganic iron salts in an alkaline environment. Four composite nanosponges were prepared by varying the content of magnetic nanoparticles (5 wt% and 10 wt%) in the cyclodextrin- and maltodextrin-based polymer matrix. The magnetic nanosponges were then characterised by FTIR, TGA, XRD, FESEM, and HRTEM analysis. The magnetic properties of the nanosponges were investigated via magnetisation curves collected at RT. Finally, the magnetic nanosponges were loaded with doxorubicin and tested as a drug delivery system. The nanosponges exhibited a loading capacity of approximately 3 wt%. Doxorubicin was released by the loaded nanosponges with sustained kinetics over a prolonged period of time.

Chitin (a biopolymer obtained from shellfish industry) was used as precursor for the production of biochars obtained via pyrolysis treatments performed at mild conditions (in the 290–540 °C range). Biochars were physicochemical characterized in order to evaluate the pyrolysis-induced effects in terms of both functional groups and material structure. Moreover, such carbonaceous materials were tested as adsorbent substrates for the removal of target molecules from aqueous environment as well as in solid-gas experiments, to measure the adsorption capacities and selectivity toward CO2. Lastly, biochars were also investigated as possible cathode materials in sustainable and low-cost electrochemical energy storage devices, such as lithium-sulphur (Li-S) batteries. Interestingly, experimental results evidenced that such chitin-derived biochars obtained via pyrolysis at mild conditions are sustainable, low-cost and easy scalable alternative materials suitable for both environmental and energetic applications.

The valorization of low-cost biobased resources (such as biomasses and their derivatives) as alternative feedstock for the preparation of innovative sustainable materials allows both economic and environmental benefits, for instance when these materials enhance the photodegradation of organic pollutants in water remediation processes. This chapter presents the physicochemical features of biobased substances (BBS) isolated from urban organic residues, and it reports on their performances as chemical auxiliaries in advanced oxidation processes (AOPs). In the homogeneous phase, BBS can indeed promote the direct oxidation of organic pollutants through the formation of many reactive species, and it can also allow running Fenton and photo-Fenton processes at circumneutral pH. Additionally, BBS can be used in heterogeneous phase. In addition, the preparation, characterization, and pollutant photodegradation efficiency of novel heterogeneous systems based on hybrid magnet-responsive materials functionalized with biobased substances is discussed, whereas the functionalization with oxidative enzymes is presented as well.

Plasmonic Nanostructures Integrated in Microfluidic Chips for the Sensitive SERS Detection of miRNAs

Pyrolysis is the simplest method to convert bio-based materials into carbonaceous chars. In this study, Na alginate (an aquatic-derived substance isolated from brown algae) is thermally treated under very mild condition (onset temperature). The effectiveness of the conversion has been determined via physicochemical characterizations, showing the possibility of modifying the (bio)polymeric chemical structure just at the beginning of its thermal degradation, guaranteeing an overall energetic beneficial effect.

Composted urban biowaste-derived substances (BBS-GC) are used as carbon sources for the preparation of carbon-coated magnet-sensitive nanoparticles obtained via co-precipitation method and the subsequent thermal treatment at 550 °C under nitrogen atmosphere. A multitechnique approach has been applied to investigate the morphology, magnetic properties, phase composition, thermal stability of the obtained magnet-sensitive materials. In particular, pyrolysis-induced modifications affecting the BBS-GC/carbon shell were highlighted. The adsorption capacity of such bio-derivative magnetic materials for the removal of hydrophobic contaminants such as polycyclic aromatic hydrocarbons was evaluated in order to verify their potential application in wastewater remediation process. The promising results suggest their use as a new generation of magnet-responsive easily-recoverable adsorbents for water purification treatments. Fil: Nisticò, Roberto. Università di Torino; Italia. Politecnico di Torino; Italia Fil: Cesano, Federico. Università di Torino; Italia Fil: Franzoso, Flavia. Università di Torino; Italia Fil: Magnacca, Giuliana. Università di Torino; Italia Fil: Scarano, Domenica. Università di Torino; Italia Fil: Funes, Israel German Aristoteles. Universidad Nacional del Comahue; Argentina Fil: Carlos, Luciano. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentina Fil: Parolo, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentina. Universidad Nacional del Comahue; Argentina

In this study, chitosan and bio-based substances (BBS) obtained from composted biowaste were used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs) via coprecipitation method. A pyrolysis treatment was carried out on both biopolymers at 550 °C, and their consequent conversion into a carbon matrix was followed by means of different physicochemical characterization techniques (mainly FTIR spectroscopy and XRD), whereas magnetic properties were evaluated by magnetization curves. The prepared materials were tested in water remediation processes from arsenic (As) species (both inorganic and organic forms). These tests, explained by means of the most common adsorption models, evidenced that the best performances were reached by both materials obtained after pyrolysis treatments, pointing out the promising application of such magnet-sensitive materials as easy-recoverable tools for water purification treatments. Fil: Nisticò, Roberto. Università di Torino; Italia. Politecnico di Torino; Italia Fil: Celi, Luisella R.. Università di Torino; Italia Fil: Bianco Prevot, Alessandra. Università di Torino; Italia Fil: Carlos, Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentina Fil: Magnacca, Giuliana. Nanostructured Interfaces And Surfaces; Italia. Università di Torino; Italia Fil: Zanzo, Elena. Università di Torino; Italia Fil: Martin, Maria. Università di Torino; Italia

Although the importance of Fe (hydr)oxides for soil organic matter (OM) stabilization and C retention by surface adsorption is well known, only recently has coprecipitation been recognized as an important process responsible for C storage in hydromorphic soils, such as rice paddy soils. Under periodic fluctuations in redox conditions the interaction between dissolved organic carbon (DOC) and Fe (hydr)oxides may not only involve organic coatings on mineral surfaces, but also Fe-DOC coprecipitates that form during the oxidation of soil solutions containing important amounts of DOC and Fe2+. The aim of this work was to provide new insights into the mechanisms involved, and the amount and selectivity of C retained during the coprecipitation process. A series of Fe-OM associations with increasing C loading was synthesized at pH 6 by surface adsorption or coprecipitation (oxidation of ferrous iron) utilizing rice-straw derived dissolved organic matter. The kinetics of Fe2+ oxidation and complexation, and the total and selective retention of DOC during the coprecipitation process were evaluated. Moreover, synthesized associations, as well as a field coprecipitate collected in situ from a paddy soil, were studied by X-ray diffraction, N2 gas adsorption-desorption isotherms, electrophoretic mobility measurements and thermogravimetric analyses. Coprecipitation resulted in higher organic C contents (49-213 mg g-1) with respect to adsorbed systems (18-47 mg g-1), and favoured the inclusion of OM within highly aggregated associations having particularly low BET specific surface areas. Coprecipitates sampled in situ also showed a similar retention of organic C confirming that this process may contribute significantly to the OM stabilization in paddy topsoils. The mechanisms involved in the retention of straw-derived DOM during coprecipitation were shown to be strongly dependent on C/Fe ratio of the solution. Although the overall coprecipitation process was highly selective for aromatic constituents, initial complexation of Fe2+ and precipitation as C-rich metal salts involved the selective interaction with aliphatic carboxylic constituents. The contribution of the latter mechanism to total C retention during coprecipitation was shown to increase with increasing solution C/Fe ratios. These aliphatic complexes formed during coprecipitation may play an important, though often underestimated, role in C stabilization in hydromorphic. The process-related selectivity of specific constituents of DOM during coprecipitation highlights the involvement of specific mechanisms, i.e. complexation, adsorption, salt precipitation, while ruling out non-selective, physical occlusion of OM within the forming coprecipitate

Introduction Several neurodegenerative brain proteinopathies, including Alzheimer's disease (AD), are associated with cerebral deposition of insoluble aggregates of α-synuclein. Previous studies reported a trend toward increased cerebrospinal fluid (CSF) α-synuclein (α-syn) concentrations in AD compared with other neurodegenerative diseases and healthy controls. Methods The pathophysiological role of CSF α-syn in asymptomatic subjects at risk of AD has not been explored. We performed a large-scale cross-sectional observational monocentric study of preclinical individuals at risk for AD (INSIGHT-preAD). Results We found a positive association between CSF α-syn concentrations and brain β-amyloid deposition measures as mean cortical standard uptake value ratios. We demonstrate positive correlations between CSF α-syn and both CSF t-tau and p-tau 181 concentrations. Discussion Animal models presented evidence, indicating that α-syn may synergistically and directly induce fibrillization of both tau and β-amyloid. Our data indicate an association of CSF α-syn with AD-related pathophysiological mechanisms, during the preclinical phase of the disease.

Web of Science art. no. 7131325

In this study, chitosan, a commercially-available linear polysaccharide mainly used as antibacterial agent, functional coating and drug-delivery system, is investigated to enlighten both water interactions and its thermal stability by using a set of complementary advanced thermal techniques, rarely applied in polysaccharides characterizations. DSC and TGA, here coupled with FTIR and GCMS analysis of the exhausted gas, were used to reveal thermal events and identify degradation products as a function of the temperature: three main steps in chitosan (N-deacetylation degree, DD = 78%) thermal degradation were highlighted and mechanism proposed. In order to make a comparison with other analogous polymeric systems and validate the results obtained, a medical grade chitosan (DD > 93%) and a commercial chitin were investigated too. Moreover, the water adsorption capacity of chitosan (DD = 78%) was followed by using thermo-microgravimetry (TMG) and the distinction between weight losses of both physically and chemically adsorbed water molecules was achieved. The approach followed allows a complete characterization of the thermal behaviors of the chitosan and highlights the need for complementary advanced thermal techniques in the detailed characterization of complex biopolymers.

The adsorption of dissolved organic carbon (DOC) on iron (Fe) (hydr)oxides represents an important stabilization mechanism for soil organic matter (OM) and contributes to soil C accumulation. However, in soils that experience periodic fluctuations in redox conditions the interaction between DOC and Fe (hydr)oxides may not only involve organic coatings on mineral surfaces, but also Fe-DOC coprecipitates that form during the oxidation of soil solutions containing important amounts of DOC and Fe 2+ . The aim of this work is to provide new insights into the mechanisms involved, and the amount and selectivity of C retained during the coprecipitation process. A series of Fe-OM associations with increasing C loading was synthesized at pH 6 by surface adsorption or coprecipitation (oxidation of ferrous iron) utilizing rice-straw derived dissolved organic matter. The kinetics of Fe 2+ oxidation and complexation, and the total and selective retention of DOC during the coprecipitation process were evaluated. Moreover, synthesized associations, as well as a field coprecipitate collected in situ from a paddy soil, were studied by X-ray diffraction, N 2 gas adsorption-desorption isotherms, electrophoretic mobility measurements and thermogravimetric analyses. Coprecipitation resulted in higher organic C contents (49–213 mg g −1 ) with respect to adsorbed systems (18–47 mg g −1 ), and favoured the inclusion of OM within highly aggregated associations having particularly low BET specific surface areas. Although coprecipitation led to a strong, selective retention of aromatic constituents, the initial complexation of Fe 2+ by aliphatic carboxylic moieties and precipitation as C-rich Fe-OM associations contributed to the total C retention, particularly at higher solution C/Fe ratios. These aliphatic complexes formed during coprecipitation may play an important, though often underestimated, role in C stabilization in soils experiencing frequent redox fluctuations and often characterized by elevated soluble Fe 2+ and DOC concentrations.

In this study, bio-based substances (BBS) obtained from composted urban biowaste are used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs). The BBS-stabilized NPs are characterized by means of different techniques (FTIR, XRD, SEM, BET analysis, magnetization curves). Additionally, TGA coupled on-line with FTIR and GC/MS analysis of the exhausted gas are performed in order to simultaneously identify all the degradation products and evaluate the exact composition of such BBS-stabilized materials. Moreover, Fenton-like or photo-Fenton-like experiments carried out at circumneutral pH are performed in order to evaluate the BBS-functionalized NPs photo-activity towards the degradation of caffeine (taken as model emerging pollutant). The obtained promising results encourage the use of BBS as a green alternative tool for the preparation of smart materials with enhanced magnet-sensitive properties, also suitable for applications in wastewater purification treatments., Facultad de Ciencias Exactas, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas

The aim of this review is to clarify the importance of surface modifications induced in biomaterials for hernia-repair application. Starting from the pioneering experiences involving proto-materials as ancient prosthesis, a historical excursus between the biomaterials used in hernioplasty was realized. Subsequently, after the revolutionary discovery of stereoregular polymerization followed by the PP application in the biomedical field performed by the surgeon F. Usher, a comparative study on different hernia-repair meshes available was realized in order to better understand all the outstanding problems and possible future developments. Furthermore, since many unsolved problems on prosthetic devices implantation are linked to phenomena occurring at the interface between the biomaterials surface and the body fluids, the importance of surface science in hernioplasty was highlighted and case studies of new surface-modified generations of prosthesis presented. The results discussed in the following evidence how the surface study are becoming increasingly important for a proper knowledge of issues related to the interaction between the living matter and the artificial prostheses.

Chitosan and pyrolyzed chitosan, acting as protective frameworks of magnetic nanoparticles (magnetite/maghemite and/or metallic Fe), have been investigated to be used in magnetically guided water remediation processes from polycyclic aromatic hydrocarbons (PAHs). Chitosan-derived magnet-sensitive materials were first obtained by a one-step coprecipitation method, and then two carbon-derived magnetic chitosan materials were obtained under N2 gas flow at 550 and 800 °C, respectively. The obtained materials were investigated by means of X-ray diffraction (XRD), FTIR spectroscopy, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), magnetic force microscopy (MFM), and magnetization measurements. Thermal treatment conditions, along with the amounts of chitosan used in the synthesis processes, played a critical role in the crystal structure and magnetic properties of the obtained nanomaterials. The adsorption capacity of chitosan-derived magnet-sensitive materials was tested toward PAHs. The results indicate high sorption capacity for anthracene and naphthalene onto the chitosan-derived material pyrolyzed at 550 °C. Furthermore, experiments performed with a mixture of eight PAHs show that PAH molecules with higher hydrophobicity and more extended aromaticity had stronger sorption capacity. Interestingly, due to the obtained results, the use of chitosan is encouraged as a platform for the creation of green adsorbents for further developments in wastewater purification treatments. Fil: Nisticò, Roberto. Università di Torino; Italia Fil: Franzoso, Flavia. Università di Torino; Italia Fil: Cesano, Federico. Università di Torino; Italia Fil: Scarano Domenica. Università di Torino; Italia Fil: Magnacca, Giuliana. Università di Torino; Italia Fil: Parolo, Maria Eugenia. Universidad Nacional del Comahue; Argentina Fil: Carlos, Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentina