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Wood is a natural composite material mainly consisting of three components, i.e., cellulose, hemicellulose, and lignin. It exhibits a complex hierarchical structure characterized by open channels, aligned in the growth direction, having specific porosity at micro-, meso-, and macro-scale, and an extended opacity, due to adsorption phenomena because of the presence of lignin and scattering, as different refractive indexes characterize its components. Even if during the historical ages some of its applications have been replaced by other materials, wood still covers a large part of common uses, which range from biomass for energy recovery to material for the building sector, or from artifacts to household/furniture manufacturing. Despite its real invention dating to 1992, only about ten years ago two independent research groups, one from the University of Maryland (USA) and the other from the Royal Institute of Technology (Sweden) rediscovered and started to thoroughly investigate the so-called transparent wood (TW). TW can be derived from almost any wood biomass through specific chemical treatments focused on lignin. These aim to completely remove this component from wood or to eliminate the chromophore groups present in the pristine material, hence obtaining, after direct densification or after infiltration with a suitable polymer resin, a new material with very high transparency, toughness, and lightness. These characteristics can further be combined with other specific features (such as environmental protection, flame retardancy, photoluminescence, and energy storage ability, among others), which open the way toward the development of new, up-to-date, advanced, and sustainable materials for both structural and functional purposes, fulfilling the current concepts of circular economy and sustainability. The present review is aimed at providing the reader with an overview of the characteristics of transparent wood, describing the latest applications and, finally, discussing some challenging issues and perspectives for possible developments in the forthcoming years.

To fulfill the current circular economy concept, the academic and industrial communities are devoting significant efforts to plastic materials’ end-of-life. Unlike thermoplastics, which are easy to recover and re-valorize, recycling thermosets is still difficult and challenging. Conversely, because of their network structure, thermosetting polymer systems exhibit peculiar features that make these materials preferable for several applications where high mechanical properties, chemical inertness, and thermal stability, among others, are demanded. In this view, vitrimers have quite recently attracted the attention of the scientific community, as they can form dynamic covalent adaptive networks that provide the properties typical of thermosets while keeping the possibility of being processed (and, therefore, mechanically recycled) beyond a certain temperature. This review aims to provide an overview of vitrimers, elucidating their most recent advances and applications and posing some perspectives for the forthcoming years.

Abstract High glucose-induced endothelial dysfunction is the early event that initiates diabetes-induced vascular disease. Here we employed Cryo Soft X-ray Tomography to obtain three-dimensional maps of high d-glucose-treated endothelial cells and their controls at nanometric spatial resolution. We then correlated ultrastructural differences with metabolic rewiring. While the total mitochondrial mass does not change, high d-glucose promotes mitochondrial fragmentation, as confirmed by the modulation of fission–fusion markers, and dysfunction, as demonstrated by the drop of membrane potential, the decreased oxygen consumption and the increased production of reactive oxygen species. The 3D ultrastructural analysis also indicates the accumulation of lipid droplets in cells cultured in high d-glucose. Indeed, because of the decrease of fatty acid β-oxidation induced by high d-glucose concentration, triglycerides are esterified into fatty acids and then stored into lipid droplets. We propose that the increase of lipid droplets represents an adaptive mechanism to cope with the overload of glucose and associated oxidative stress and metabolic dysregulation.

Objective: The prevalence of food allergies (FA) has increased worldwide over the last few decades. Milk, eggs, and peanuts are among the most common allergens and can cause anaphylaxis. Therefore, we aimed to identify biomarkers that could predict the persistence and/or severity of IgE-mediated allergies to milk, eggs, and peanuts via a systematic review. Methods: This systematic review proceeded according to a protocol registered in the International Prospective Register of Systematic Reviews. Two independent authors extracted studies of interest from PubMed, SciELO, EMBASE, Scopus, and Ebsco databases and assessed their quality using the Newcastle-Ottawa Scale. Results: We selected 14 articles describing 1,398 patients. Among eight identified biomarkers, total IgE, specific IgE (sIgE), and IgG4 were the most often cited biomarkers of persistent allergies to milk, eggs, and peanuts. Skin prick tests, endpoint tests, and sIgE cutoff levels may predict positive responses to challenges with these foods. The basophil activation test is a biomarker for the severity and/or threshold of allergic reactions to milk and peanuts. Conclusion: Only a few publications identified possible prognostic indicators of the persistence or severity of FA and outcomes of oral food challenges, indicating that more accessible biomarkers are needed to determine the likelihood of having a severe food allergic reaction.

[Propósito] O presente artigo busca analisar as perspectivas regulatórias do setor de saneamento básico diante da atribuição de competência à Agência Nacional de Águas e Saneamento Básico - ANA, pela Lei Federal nº 14.026/2020, para editar norma de referência de governança regulatória a ser observada pelas agências infranacionais em sua atuação. [Metodologia/abordagem/design] O artigo meditará acerca dos desafios para implementação prática de tal norma de referência. [Resultados] São suscitadas algumas proposições sobre as linhas gerais da futura norma de referência sobre o tema, a ser elaborada pela ANA no ano de 2022, conforme sua agenda regulatória.

In the early years of school, pupils have a very positive approach towards any new topic. Very often, the first contact with mathematics in the Italian school risks giving a limited and somehow negative impression, generating long-lasting effects. In this paper, we report on a series of experiences carried out in a second-year class of a primary school that allowed us to introduce new concepts and approaches through games and puzzles. The aim was to stimulate the creativity and empower pupils. We have used simple materials and applied the "Puzzle-Based Learning" method. Despite the limited time devoted to this experience, the outcomes have been extremely positive.