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Abstract In the expanding field of high‐performance materials, polymer‐based thermoset composites play an important role due to their favorably‐high strength/weight ratio and their mechanical performance, thermal stability, and chemical resistance. However, their chemically‐crosslinked nature hampers their re‐processability and efficient recyclability, thus making them not compliant with the principles of the circular economy and of end‐of‐life valorization. Dynamic covalent polymers able to modify their network topology upon thermal stimulus can be considered valid alternatives to commonly used thermosets as they offer advantages in terms of recyclability and reusability, normally not achievable with conventional cross‐linked systems. Within the broad field of dynamic polymers, thermally‐triggered Diels‐Alder based materials represent reliable platforms with enormous technological and industrial potential as repairable, reusable and recyclable matrices in composites given their chemical versatility, suitable mechanical performance and ease of production and processing. In this review, a comprehensive discussion of the most recent demonstrations of the reversibility, reprocessability and recyclablability of such systems is provided, in the context of their use as polymer matrices in composites. It is hoped that this work will stimulate further discussion and research in the area of reversible polymer composites with increased functionality and extended lifetime, in view of their application in future circular economy scenarios.

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In the present work, rice husks (RHs), which, worldwide, represent one of the most abundant agricultural wastes in terms of their quantity, have been treated and fractionated in order to allow for their complete valorization. RHs coming from the raw and parboiled rice production have been submitted at first to a hydrothermal pretreatment followed by a deep eutectic solvent fractionation, allowing for the separation of the different components by means of an environmentally friendly process. The lignins obtained from raw and parboiled RHs have been thoroughly characterized and showed similar physico-chemical characteristics, indicating that the parboiling process does not introduce obvious lignin alterations. In addition, a preliminary evaluation of the potentiality of such lignin fractions as precursors of cement water reducers has provided encouraging results. A fermentation-based optional preprocess has also been investigated. However, both raw and parboiled RHs demonstrated a poor performance as a microbiological growth substrate, even in submerged fermentation using cellulose-degrading fungi. The described methodology appears to be a promising strategy for the valorization of these important waste biomasses coming from the rice industry towards a circular economy perspective.

Over the past decade, rapid developments and advancements in the electronic industry have led to a sharp increase in electronic waste (e-waste) disposed in landfills and not reusable. A wide and diversified range of advanced materials are present in e-waste. Among them, polymer nanocomposites represent a valuable example of high-added-value materials that can have however negative environmental consequences. Although thermoset polymer nanocomposites have demonstrated various beneficial properties such as high chemical resistance, and good mechanical strength, owing to their covalently crosslinked network, their potential damage could shorten the lifespan of electronic devices, increasing the amount of e-waste. To extend their service life, polymer matrices with self-healing abilities, and a good recovery of mechanical properties after healing have been developed. In this context, polymer matrices with dynamic covalent bonds activated by a thermal stimulus stand out as an attractive choice because they combine the re-processability of thermoplastics with the high mechanical performance of thermoset polymers. This chapter will discuss two emerging categories of polymer matrices with thermally reversible covalent bonds: Diels-Alder (DA)- and vitrimer-based systems. Within these two classes of dynamic polymer nanocomposites, the focus will be on the reaction mechanisms enabling self-healing, the types of nanofillers used, the recovery of mechanical and functional properties after damage, and the potential applications in devices and sensors. This work will therefore foster new studies and discussions in the field of repairable electronic and functional devices to prolong their lifetime and reduce their environmental impact. [ABSTRACT FROM AUTHOR]

Luminescent solar concentrators (LSCs) are spectral conversion devices offering interesting opportunities for the integration of photovoltaics into the built environment and portable systems. The Förster‐resonance energy transfer (FRET) process can boost the optical response of LSCs by reducing energy losses typically associated to non‐radiative processes occurring within the device under operation. In this work, a new class of FRET‐based thin‐film LSC devices is presented, in which the synthetic versatility of linear polyurethanes (PU) is exploited to control the photophysical properties and the device performance of the resulting LSCs. A series of luminescent linear PUs are synthesized in the presence of two novel bis‐hydroxyl‐functionalized luminophores of suitable optical properties, used as chain extenders during the step‐growth polyaddition reaction for the formation of the linear macromolecular network. By synthetically tuning their composition, the obtained luminescent PUs can achieve a high energy transfer efficiency (≈90%) between the covalently linked luminophores. The corresponding LSC devices exhibit excellent photonic response, with external and internal photon efficiencies as high as ≈4% and ≈37%, respectively. Furthermore, their optimized power conversion efficiency combined with their enhanced average visible‐light transmittance highlight their suitability for potential use as transparent solar energy devices. [ABSTRACT FROM AUTHOR]

Falls are common in patients with neurological diseases and can be very problematic. Recently, there has been an increase in fall prevention research in people with neurological diseases; however, these studies are usually condition-specific (e.g., only MS, PD or stroke). Here, our aim was to evaluate and compare the efficacy of an advanced and innovative dual-task, motor-cognitive rehabilitation program in individuals with different neurological diseases who are at risk of falling. We recruited 95 consecutive adults with neurological diseases who are at risk of falling and divided them into four groups: 31 with cerebrovascular disease (CVD), 20 with Parkinson’s disease (PD), 23 with traumatic brain injury (TBI) and 21 with other neurological diseases (OND). Each patient completed a dual-task, motor-cognitive training program and underwent two test evaluations to assess balance, gait, fear of falling and walking performance at the pre-and post-intervention. We found that our experimental motor-cognitive, dual-task rehabilitation program was an effective method for improving walking balance, gait, walking endurance and speed, and fear of falling, and that it reduced the risk of falls in patients with different neurological diseases. This study presents an alternative approach for people with chronic neurological diseases and provides innovative data for managing this population.

En los últimos años, los crecientes desarrollos en el campo de la Inteligencia Artificial se han convertido en uno de los principales motores de innovación tecnológica. Sin embargo, su aplicación en diversos tipos de sistemas de armas comienza a poner de relieve las problemáticas fundamentales de su uso en los escenarios de conflicto tanto actuales como futuros. A partir de un análisis profundo, este trabajo estudia una serie de puntos sobre los cuales la utilización de los Sistemas de Armas Autónomas Letales puede generar controversia. Partiendo desde la tecnología como factor disruptivo en el campo de batalla, pasando por los problemas conceptuales en la definición de la Inteligencia Artificial, recorriendo los dilemas éticos y jurídicos en el uso de estos sistemas, arribando hasta las implicancias de su utilización en el escenario internacional, llegamos a la conclusión de que el uso de estos sistemas traería consigo un proceso de “deshumanización de la guerra”.

The severity of coronavirus disease 2019 (COVID-19) may be influenced by pre-existing immune responses against endemic coronaviruses, but conflicting data have been reported. We studied 148 patients who were hospitalised because of a confirmed diagnosis of COVID-19, classified mild in 58, moderate in 44, and severe in 46. The controls were 27 healthy subjects. At admission, blood samples were collected for the measurement of biomarkers of disease severity and levels of the IgG against the receptor-binding domain (RBD) of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and pre-existing coronaviruses OC43, HKU1, NL63 and 229E. Higher levels of IgG antibodies against the RBD of pre-existing coronavirus (with the highest significance for anti-HKU1 IgG, p = 0.01) were found in patients with mild disease, compared with those with moderate or severe disease. Multivariable logistic regression confirmed the association of high levels of antibodies to pre-existing coronavirus with mild disease and showed their associations with low levels of the complement activation marker SC5b-9 (p range = 0.007–0.05). High levels of anti-NL63 antibodies were associated with low levels of the coagulation activation marker D-dimer (p = 0.04), while high levels of IgG against 229E were associated with low levels of the endothelial activation marker von Willebrand factor (p = 0.05). Anti-SARS-CoV-2-neutralising activity of plasma positively correlated with anti-SARS-CoV-2 IgG (r = 0.53, p = 0.04) and with anti-HKU1 IgG (r = 0.51, p = 0.05). In hospitalised patients with COVID-19, high levels of antibodies to pre-existing coronaviruses are associated with mild disease, suggesting that their measurement could be useful in predicting the severity of the disease.

In the present work, brewers’ spent grain (BSG), which represents the major by-product of the brewing industry, was recovered from a regional brewery and fractionated in order to obtain a complete valorization. In particular, the whole process was divided in two main parts. A first pretreatment with hot water in an autoclave allowed the separation of a solution containing the soluble proteins and sugars, which accounted for 25% of the total starting biomass. This first step allowed the preparation of a medium that was successfully employed as a valuable growing medium for different microbial fermentations, leading to valuable fungal biomass as well as triglycerides with a high content of linear or branched fatty acids, depending on the microorganism used. The solid water-insoluble residue was then submitted to a lignocellulose deep eutectic solvent-mediated fractionation, which allowed the recovery of two important main fractions: BSG cellulose and BSG lignin. The latter product was tested as potential precursor for the development of cement water reducers with encouraging results. This combination of treatments of the waste biomass appeared to be a promising sustainable strategy for the development of the full exploitation of BSG from a circular economy perspective.