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Questo testo si rivolge a chiunque sia interessato ad approfondire la riflessione sulla chimica vista nella sua accezione più ampia e profonda: espressione culturale e sistema di pensiero sul mondo materiale. Nato dalla collaborazione tra esperti di diversi campi disciplinari e professionali (docenti e ricercatori in didattica chimica, pedagogia, epistemologia, didattica generale e insegnanti della scuola secondaria di secondo grado) per presentare e analizzare gli aspetti fondamentali della disciplina chimica e del suo insegnamento, ha l’obiettivo di promuovere una didattica mirata all’apprendimento significativo. Si propone pertanto come strumento al servizio di chi si avvicina all’insegnamento della chimica attraverso i nuovi percorsi di formazione per insegnanti, ma anche di chi desidera rivedere, in un’ottica diversa, gli insegnamenti già in atto nei diversi gradi di formazione, dalla primaria all’università.

Synthetic therapeutic peptides (STP) are intensively studied as new-generation drugs, characterized by high purity, biocompatibility, selectivity and stereochemical control. However, most of the studies are focussed on the bioactivity of STP without considering how the formulation actually used for therapy administration could alter the physico-chemical properties of the active principle. The aggregation properties of a 20-mer STP (Ac-His-Ala-Arg-Ile-Lys-D-Pro-Thr-Phe-Arg-Arg-D-Leu-Lys-Trp-Lys-Tyr-Lys-Gly-Lys-Phe-Trp-NH2 ), showing antitumor activity, were investigated by optical spectroscopy and atomic force microscopy imaging, as itself (CIGB552) and in its therapeutic formulation (CIGB552TF). It has found that the therapeutic formulation deeply affects the aggregation properties of the investigated peptide and the morphology of the aggregates formed on mica by deposition of CIGB552 and CIGB552TF millimolar solutions. Molecular dynamics simulations studied the first steps of CIGB552 aggregation under physiological ionic strength conditions (NaCl 150 mM), showing that peptide oligomers, from dimers to tetramers, are preferentially formed in this environment. Interestingly, cell viability assays performed on H-460 cell lines indicate a major antiproliferative activity of the peptide in its therapeutic formulation with respect to the peptide aqueous solution.

Self‐assembled structures obtained from organic molecules have shown great potential for applications in a wide range of domains. In this context, short peptides prove to be a particularly versatile class of organic building blocks for self‐assembled materials. These species afford the biocompatibility and polymorphic richness typical of proteins while allowing synthetic availability and robustness typical of smaller molecules. At the nano‐to‐mesoscale, the architectures obtained from peptide units exhibit stability and a large variety of morphologies, the most common of which are nanotubes, nanoribbons, and nanowires. This review describes the formation of peptide‐based self‐assembled structures triggered by different stimuli (e.g., ionic strength, pH, and polarity), and the interactions that drive the assembling processes. It is surveyed how judicious molecular design is exploited to impart favourable assembling properties to afford systems with desired characteristics. A large body of literature provides the experimental and in silico data to predict self‐assembly in a given peptide system and obtain different supramolecular organizations for applications in a wide range of fields, from transport to sensing, from catalysis to drug delivery and tissue regeneration.

Online video constitutes the largest, continuously growing portion of the Web content. Web users drive this growth by massively sharing their personal stories on social media platforms as compilations of their daily visual memories, or with animated GIFs and memes based on existing video material. Therefore, it is crucial to gain understanding of the semantics of video stories, i.e., what do they capture and how. The remix of visual content is also a powerful way of understanding the implicit aspects of storytelling, as well as the essential parts of audio-visual (AV) material. In this paper we take a digital hermeneutics approach to understand what are the visual attributes and semantics that drive the creation of narratives. We present insights from a nichesourcing study in which humanities scholars remix keyframes and video fragments into micro-narratives i.e., (sequences of) GIFs. To support the narrative creation for humanities scholars a specific video annotation is needed, e.g., (1) annotations that consider literal and abstract connotations of video material, and (2) annotations that are coarse-grained, i.e., focusing on keyframes and video fragments as opposed to full length videos. The main findings of the study are used to facilitate the automatic creation of narratives in the digital humanities exploratory search tool DIVE+

Online video constitutes the largest, continuously growing portion of the Web content. Web users drive this growth by massively sharing their personal stories on social media platforms as compilations of their daily visual memories, or with animated GIFs and memes based on existing video material. Therefore, it is crucial to gain understanding of the semantics of video stories, i.e., what do they capture and how. The remix of visual content is also a powerful way of understanding the implicit aspects of storytelling, as well as the essential parts of audio-visual (AV) material. In this paper we take a digital hermeneutics approach to understand what are the visual attributes and semantics that drive the creation of narratives. We present insights from a nichesourcing study in which humanities scholars remix keyframes and video fragments into micro-narratives i.e., (sequences of) GIFs. To support the narrative creation for humanities scholars a specific video annotation is needed, e.g., (1) annotations that consider literal and abstract connotations of video material, and (2) annotations that are coarse-grained, i.e., focusing on keyframes and video fragments as opposed to full length videos. The main findings of the study are used to facilitate the automatic creation of narratives in the digital humanities exploratory search tool DIVE+

The implausibility of the extreme rationality assumptions of Nash equilibrium has been attested by numerous experimental studies with human players. In particular, the fundamental social dilemmas such as the Traveler's dilemma, the Prisoner's dilemma, and the Public Goods game demonstrate high rates of deviation from the unique Nash equilibrium, dependent on the game parameters or the environment in which the game is played. These results inspired several attempts to develop suitable solution concepts to more accurately explain human behaviour. In this line, the recently proposed notion of cooperative equilibrium [5, 6], based on the idea that players have a natural attitude to cooperation, has shown promising results for single-shot games. In this paper, we extend this approach to iterated settings. Specifically, we define the Iterated Cooperative Equilibrium (ICE) and show it makes statistically precise predictions of population average behaviour in the aforementioned domains. Importantly, the definition of ICE does not involve any free parameters, and so it is fully predictive.