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Microplastic pollution is a widespread threat for marine fauna. Mussels are good candidates for assessment of microplastic exposure in the environment because of their wide geographical and spatial distribution and their filtration system. In this work the 65% of analysed mussels assessed the presence of microfibres in their tissue, with an amount ranged from 0.0 to 4.3 MF/ g ww. This result confirm that mussels could be used as biomonitors of surrounding environment pollution.

Contribution of ECOBULK project to PolyChar27, the 27th World Forum on Advanced Materials held in Naples on October 14-17 2019. Title of the contribution "Characterization of end-of-life materials from construction, automotive and furniture sectors to evaluate their recyclability". The files include the report of the forum, the book of the forum and the poster exposing the ECOBULK contribution.

Microplastics have been recently identified as one of the most concerning new class of pollutants, extensively found in various environments. They have been defined as plastic fragments smaller than 5 mm, coming from several sources. The most unexpected source of microplastic pollution is certainly the washing processes of synthetic textiles, that was estimated as a major contributor to the emission of microplastics into global oceans. Due to the mechanical and chemical stresses that fabrics undergo during a washing process in a laundry machine, microfibres detach from the yarn and, through the wastewater, end up in the marine environment. Sampling of marine sediments showed that polyester, acrylic, polypropylene, and polyamide fibres contaminate shores on a global-scale. Their impact on marine flora and fauna is unpredictable and quite dangerous since they can adsorb organic pollutants and be ingested by marine organisms, potentially reaching the human food web. In this work, innovative surface treatments of synthetic fabrics were developed to mitigate the release of microplastics during their washing. The aim was to create a protective coating on the fabric surface, which can protect clothes during washing processes, then reducing the amount of microfibres released. Instead of using conventional synthetic textile auxiliaries, these treatments involve the usage of alternative polymers, selected for their biocompatibility and eco-sustainability. Two different strategies were explored to develop such surface treatments on polyamide 6.6. fabrics. The first one is based on the application of pectin, a natural polysaccharide, that was chemically modified by reaction with glycidyl methacrylate (GMA), whose vinylic groups were exploited to graft pectin on the surface of the polyamide fabric.1 The second treatment is based on the application of an electrofluidodynamic (EFD) method to deposit on the fabric a countinuous layer made of biodegradable polymers from biosources - i.e., polylactic acid (PLA) and polybutylene succinate adipate (PBSA).2,3 The treated fabrics underwent different analysis to evaluate the coating morphology and possible changes to fabric properties. Among the tecniques used there are scanning electron microscopy (SEM), attenuated total reflectance (ATR) Fourier Transform InfraRed (FTIR) spectroscopy and thermogravimetric analysis (TGA). Finally, washing tests were performed to evaluate the effectiveness of the finishing treatments in mitigating the release of microplastics during the washing of fabric and the outcomes revealed that all treatments decreased of more than 80% the release of microfibres with respect to untreated fabrics.

The global textile production is mainly based on synthetic fibres like polyester, polyamide, polyacrylic and polypropylene. Recently, the washing process of synthetic clothes has been identified as a source of microplastics, plastic fragments smaller than 5 mm, that pollute marine ecosystems. In fact, the mechanical stresses and the friction of the detergent cause the detachment of microfibres from the yarns. In such scenario, the aim of this work is to develop functional finishing treatments that can protect the fabric during the washing, preventing in this way the release of microplastics. As alternative to synthetic polymers, pectin, a natural polysaccharide, was used to create a coating on polyamide fabrics. Pectin was chemically modified by the reaction with glycidyl methacrylate (GMA), whose vinyl groups were used to graft pectin on the surface of the fabric. A key point was the realization of a homogeneous coating, that did not modify the hand of the textile. For this aim, different ratios of pectin:GMA were tested and the treated fabrics were analysed by scanning electron microscopy (SEM), solid state nuclear magnetic resonance spectroscopy (NMR) and Attenuated Total Reflectance (ATR) Fourier Transform InfraRed (FT-IR) spectroscopy, in order to evaluate the effectiveness of the finishing treatments.

In this work the results of effects induced by a dry ball milling process on cellulose structure, morphology and properties are reported, together with results on the preparation of new polycaprolactone (PCL) based composites prepared with unmodified and ball milled cellulose.

Nowadays nanotechnologies applied to the food packagingsector find always more applications due to a wide range of benefits that they can offer, such as improved barrier properties, improved mechanical performance, antimicrobial properties and so on. Recently many researches are addressed to the set up of new food packagingmaterials, in which polymer nanocomposites incorporate nanosensors, developing the so-called "smart" packaging. Some examples of nanocomposite sensors specifically realised forthe food packagingindustry are reported. The second part of this work deals with the preparation and characterisation of two new polymer-based nanocomposite systems that can be used as food packagingmaterials. Particularly the results concerning the following systems are illustrated: isotactic polypropylene (iPP) filled with CaCO(3) nanoparticles and polycaprolactone (PCL) filled with SiO(2) nanoparticles.

Nanocomposites of polyaniline (PANI) and two carbon nanostructures - multiwall carbon nanotubes (MWCNTs) and graphene G) were obtained by electrochemical polymerization. PANI based nanocomposites with different concentration of carbon nanostructures (CNS:1, 2 and 3wt%) as well as with different methods for CNS dispersion in the electrolyte, were synthesized. The interactions among the CNS nanostructures and polyaniline matrix were studied and the results confirmed strong interactions among the quinoidal structure of PANI and both CNS. In order to design nanocomposite sensors, PANI/CNS nanocomposites were directly electro-polymerized on gold wires of screen printed electrodes. Their sensing activity was evaluated through the resistivity changes at different pH.

Humans are estimated to consume several grams per week of nanoplastics (NPs) through exposure to a variety of contamination sources. Nonetheless, the effects of these polymeric particles on living systems are still mostly unknown. Here, by means of CD, NMR and TEM analyses, we describe at an atomic resolution the interaction of ubiquitin with polystyrene NPs (PS-NPs), showing how a hard protein corona is formed. Moreover, we report that in human HeLa cells exposure to PS-NPs leads to a sensible reduction of ubiquitination. Our study overall indicates that PS-NPs cause significant structural effects on ubiquitin, thereby influencing one of the key metabolic processes at the base of cell viability.

Background Metabolic reprogramming is an important issue in tumor biology. A recently-identified actor in this regard is the molecular chaperone TRAP1, that is considered an oncogene in several cancers for its high expression but an oncosuppressor in others with predominant oxidative metabolism. TRAP1 is mainly localized in mitochondria, where it interacts with respiratory complexes, although alternative localizations have been described, particularly on the endoplasmic reticulum, where it interacts with the translational machinery with relevant roles in protein synthesis regulation. Results Herein we show that, inside mitochondria, TRAP1 binds the complex III core component UQCRC2 and regulates complex III activity. This decreases respiration rate during basal conditions but allows sustained oxidative phosphorylation when glucose is limiting, a condition in which the direct TRAP1-UQCRC2 binding is disrupted, but not TRAP1-complex III binding. Interestingly, several complex III components and assembly factors show an inverse correlation with survival and response to platinum-based therapy in high grade serous ovarian cancers, where TRAP1 inversely correlates with stage and grade and directly correlates with survival. Accordingly, drug-resistant ovarian cancer cells show high levels of complex III components and high sensitivity to complex III inhibitory drug antimycin A. Conclusions These results shed new light on the molecular mechanisms involved in TRAP1-dependent regulation of cancer cell metabolism and point out a potential novel target for metabolic therapy in ovarian cancer.

Oncogene-induced senescence (OIS) is a form of stable cell-cycle arrest arising in response to oncogenic stimulation. OIS must be bypassed for transformation, but the mechanisms of OIS establishment and bypass remain poorly understood, especially at the post-transcriptional level. Here, we show that the RNA-binding protein UNR/CSDE1 enables OIS in primary mouse keratinocytes. Depletion of CSDE1 leads to senescence bypass, cell immortalization, and tumor formation, indicating that CSDE1 behaves as a tumor suppressor. Unbiased high-throughput analyses uncovered that CSDE1 promotes OIS by two independent molecular mechanisms: enhancement of the stability of senescence-associated secretory phenotype (SASP) factor mRNAs and repression of Ybx1 mRNA translation. Importantly, depletion of YBX1 from immortal keratinocytes rescues senescence and uncouples proliferation arrest from the SASP, revealing multilayered mechanisms exerted by CSDE1 to coordinate senescence. Our data highlight the relevance of post-transcriptional control in the regulation of senescence. We thank Bill Keyes and members of his lab Mekayla Storer, Birgit Ritschka, and Alba Mas for expert advice and help at the initial stages of this project. We also thank Jernej Ule for sharing reagents and expertise on iCLIP, Ola Larsson for guidance on anota2seq, and Bill Keyes and Juan Valcárcel for carefully reading the manuscript. We acknowledge Raquel García Olivas of the CRG Advanced Light Microscopy Unit (ALMU) for her support and assistance in this work. We thank the CRG Bioinformatics Unit, the CRG Genomics Facility, the CRG/UPF FACS Unit, and the IRB Histopathology Facility for high-throughput sequencing and analysis, cell sorting, and histopathology analysis, respectively. M.I.-F. and A.C. were supported by FPI fellowships from the Spanish Ministry of Science and Innovation (MICINN) . F.G. was supported by grants from MICINN ( PGC2018-099697-B-I00 and BFU2015-68741 ), “La Caixa” Foundation (ID 100010434 ) under the agreement LCF/PR/HR17/52150016, the Catalan Agency for Research and Universities ( 2017SGR534 ), and the Centre of Excellence Severo Ochoa.

Extensive metabolic remodeling is a fundamental feature of cancer cells. Although early reports attributed such remodeling to a loss of mitochondrial functions, it is now clear that mitochondria play central roles in cancer development and progression, from energy production to synthesis of macromolecules, from redox modulation to regulation of cell death. Biosynthetic pathways are also heavily affected by the metabolic rewiring, with protein synthesis dysregulation at the hearth of cellular transformation. Accumulating evidence in multiple organisms shows that the metabolic functions of mitochondria are tightly connected to protein synthesis, being assembly and activity of respiratory complexes highly dependent on de novo synthesis of their components. In turn, protein synthesis within the organelle is tightly connected with the cytosolic process. This implies an entire network of interactions and fine-tuned regulations that build up a completely under-estimated level of complexity. We are now only preliminarily beginning to reconstitute such regulatory level in human cells, and to perceive its role in diseases. Indeed, disruption or alterations of these connections trigger conditions of proteotoxic and energetic stress that could be potentially exploited for therapeutic purposes. In this review, we summarize the available literature on the coordinated regulation of mitochondrial and cytosolic mRNA translation, and their effects on the integrity of the mitochondrial proteome and functions. Finally, we highlight the potential held by this topic for future research directions and for the development of innovative therapeutic approaches.

Microplastics released from textiles during the washing process represent the most prevalent type of microparticles found in different environmental compartments and ecosystems around the world. Release of microfibres during the washing process of synthetic textiles is due to the mechanical and chemical stresses that clothes undergo in washing machines. Several washing process parameters, conditions, formulations of laundering additives have been correlated to microfibre release and some of them have been identified to affect microfibre release during washing process, while no correlation has been evaluated between microfibre release and washing load. In the present study, microfibre release was evaluated as function of the washing load in a real washing process, indicating a progressive decrease of microfibre release with increasing washing load. The quantity of released microfibres increased by around 5 times by decreasing the washing load due to a synergistic effect between water-volume to fabric ratio and mechanical stress during washing. Moreover, the higher mechanical stress to which the fabric is subjected in the case of a low washing load, hinders the discrimination of the effect on the release of other washing parameters like the type of detergent and laundry additives used.

Lin28 is an evolutionary conserved RNA-binding protein that plays important roles during embryonic development and tumorigenesis. It regulates gene expression through two different post-transcriptional mechanisms. The first one is based on the regulation of miRNA biogenesis, in particular that of the let-7 family, whose expression is suppressed by Lin28. Thus, loss of Lin28 leads to the upregulation of mRNAs that are targets of let-7 species. The second mechanism is based on the direct interaction of Lin28 with a large number of mRNAs, which results in the regulation of their translation. This second mechanism remains poorly understood. To address this issue, we purified high molecular weight complexes containing Lin28a in mouse embryonic stem cells (ESCs). Numerous proteins, co-purified with Lin28a, were identified by proteomic procedures and tested for their possible role in Lin28a-dependent regulation of the mRNA encoding DNA methyltransferase 3a (Dnmt3a). The results show that Lin28a activity is dependent on many proteins, including three helicases and four RNA-binding proteins. The suppression of four of these proteins, namely Ddx3x, Hnrnph1, Hnrnpu or Syncrip, interferes with the binding of Lin28a to the Dnmt3a mRNA, thus suggesting that they are part of an oligomeric ribonucleoprotein complex that is necessary for Lin28a activity.

Metabolic reprogramming, carried out by cancer cells to rapidly adapt to stress such as hypoxia and limited nutrient conditions, is an emerging concepts in tumor biology, and is now recognized as one of the hallmarks of cancer. In contrast with conventional views, based on the classical Warburg effect, these metabolic alterations require fully functional mitochondria and finely-tuned regulations of their activity. In turn, the reciprocal regulation of the metabolic adaptations of cancer cells and the microenvironment critically influence disease progression and response to therapy. This is also realized through the function of specific stress-adaptive proteins, which are able to relieve oxidative stress, inhibit apoptosis, and facilitate the switch between metabolic pathways. Among these, the molecular chaperone tumor necrosis factor receptor associated protein 1 (TRAP1), the most abundant heat shock protein 90 (HSP90) family member in mitochondria, is particularly relevant because of its role as an oncogene or a tumor suppressor, depending on the metabolic features of the specific tumor. This review highlights the interplay between metabolic reprogramming and cancer progression, and the role of mitochondrial activity and oxidative stress in this setting, examining the possibility of targeting pathways of energy metabolism as a therapeutic strategy to overcome drug resistance, with particular emphasis on natural compounds and inhibitors of mitochondrial HSP90s.

Hexamethylenediamine (HMDA) and other long chain aliphatic diamines can induce substrate-independent polymer film deposition from dopamine and several other catechols substrates at relatively low concentrations, however the mechanism of the diamine-promoted effect has remained little understood. Herein, we report data indicating that: (a) film deposition from 1 mM HMDA and dopamine is not affected by chemical oxidation with periodate but is markedly inhibited by resorcinol, which also prevents PDA film formation at 10 mM monomer concentration in the absence of HMDA; (b) N-acetylation of HMDA completely inhibits the effect on PDA film formation; (c) HMDA enables surface functionalization with 1 mM 5,6-dihydroxyindole (DHI) polymerization at pH 9.0 in a resorcinol-inhibitable manner. Structural investigation of the polymers produced from dopamine and DHI in the presence of HMDA using solid state 13C and 15N NMR and MALDI-MS suggested formation of covalent cross linked structures. It is concluded that HMDA enhances polydopamine adhesion by acting both on dopamine quinone and downstream, e.g., via covalent coupling with DHI. These results provide new insights into the mechanisms of PDA adhesion and disclose resorcinol as a new potent tool for targeting/mapping quinone intermediates and for controlling polymer growth. Hexamethylenediamine (HMDA) and other long chain aliphatic diamines can induce substrate-independent polymer film deposition from dopamine and several other catechols substrates at relatively low concentrations, however the mechanism of the diamine-promoted effect has remained little understood. Herein, we report data indicating that: (a) film deposition from 1 mM HMDA and dopamine is not affected by chemical oxidation with periodate but is markedly inhibited by resorcinol, which also prevents PDA film formation at 10 mM monomer concentration in the absence of HMDA; (b) N-acetylation of HMDA completely inhibits the effect on PDA film formation; (c) HMDA enables surface functionalization with 1 mM 5,6-dihydroxyindole (DHI) polymerization at pH 9.0 in a resorcinol-inhibitable manner. Structural investigation of the polymers produced from dopamine and DHI in the presence of HMDA using solid state C-13 and N-15 NMR and MALDI-MS suggested formation of covalent cross linked structures. It is concluded that HMDA enhances polydopamine adhesion by acting both on dopamine quinone and downstream, e.g., via covalent coupling with DHI. These results provide new insights into the mechanisms of PDA adhesion and disclose resorcinol as a new potent tool for targeting/mapping quinone intermediates and for controlling polymer growth.

Syndesmos (SDOS) is a functionally poorly characterized protein that directly interacts with p53 binding protein 1 (53BP1) and regulates its recruitment to chromatin. We show here that SDOS interacts with another important cancer-linked protein, the chaperone TRAP1, associates with actively translating polyribosomes and represses translation. Moreover, we demonstrate that SDOS directly binds RNA in living cells. Combining individual gene expression profiling, nucleotide crosslinking and immunoprecipitation (iCLIP), and ribosome profiling, we discover several crucial pathways regulated post-transcriptionally by SDOS. Among them, we identify a small subset of mRNAs responsible for the biogenesis of primary cilium that have been linked to developmental and degenerative diseases, known as ciliopathies, and cancer. We discover that SDOS binds and regulates the translation of several of these mRNAs, controlling cilia development.

The compendium of RNA-binding proteins (RBPs) has been greatly expanded by the development of RNA-interactome capture (RIC). However, it remained unknown if the complement of RBPs changes in response to environmental perturbations and whether these rearrangements are important. To answer these questions, we developed “comparative RIC” and applied it to cells challenged with an RNA virus called sindbis (SINV). Over 200 RBPs display differential interaction with RNA upon SINV infection. These alterations are mainly driven by the loss of cellular mRNAs and the emergence of viral RNA. RBPs stimulated by the infection redistribute to viral replication factories and regulate the capacity of the virus to infect. For example, ablation of XRN1 causes cells to be refractory to SINV, while GEMIN5 moonlights as a regulator of SINV gene expression. In summary, RNA availability controls RBP localization and function in SINV-infected cells. Garcia-Moreno, Noerenberg, Ni, and colleagues developed “comparative RNA-interactome capture” to analyze the RNA-bound proteome during virus infection. More than 200 cellular RNA-binding proteins change their binding activity in response to this challenge, mainly driven by transcript availability. Many of these RNA-binding proteins regulate viral replication and can be targeted to influence infection outcome., European Union’s Horizon 2020 research and innovation programme under Marie-Sklodowska-Curie grant agreement 700184. I.D. is funded by Wellcome Trust Investigator Award 209412/Z/17/Z. V.P. is funded by a SciLifeLab Fellowship, the Swedish Research Council (VR 2016-01842), a Wallenberg Academy Fellowship (KAW 2016.0123), and the Ragnar Söderberg Foundation. L.C. is funded by grant DGICYT SAF2015-66170-R (MINECO/FEDER).

The polar functionalization of vinylbenzyl chloride hyper-crosslinked (HCL) resins with ethanolamine at variable functionalization extent is reported. The functionalization reaction was investigated by a multitechnique approach to confirm the reaction mechanism and to calculate the yield of functionalization. Increasing the amount of ethanolamine grafted onto the HCL resin, the total pore volume of the resins decreased, while the microporous fraction increased and the pore size distribution evolved from bimodal to unimodal. The effect of the functionalization on the adsorption properties of the resins was investigated for CO2 sequestration and water purification applications. Both CO2 adsorption capacity and phenol removal efficiency from water solutions over the total pore volume of the resins were significantly improved. Moreover, the CO2/N2 selectivity significantly increased for the HCL resin at intermediate functionalization degree, which represents the optimal trade-off between high functionalization extent and porosity distribution evolution.

Composites based on poly(butylene succinate-co-butylene adipate) (PBSA) containing amorphized and crystalline cellulose reinforcements have been prepared and characterized. In order to improve the polymer/filler interfacial adhesion, an efficient compatibilizing agent has been synthesized by chemical modification of PBSA and characterized by FT-IR, FT-NIR and 1H NMR spectroscopy. Uncompatibilized and compatibilized composites have been tested through morphological, mechanical, calorimetric and thermogravimetric analysis. Moreover, water vapor permeability and biodegradation kinetics of composites have been investigated. The addition to PBSA of cellulose fillers differing from each other by crystallinity degree and morphology, and the use of a compatibilizing agent have allowed modulating tensile and thermal properties, water vapor transmission rate and biodegradation kinetic of the composites.

Washing processes of synthetic clothes have been identified as the main source of microplastic pollution in marine ecosystems. Textile microfibres have been found in marine sediments and organisms, posing a real threat for the environment. The development of mitigation approaches is strongly needed to prevent the impact of microplastics. In this work, an innovative finishing treatment of polyamide fabrics is proposed to mitigate the microplastic impact, by preventing the damage of fabrics during washings. The treatment is based on the use of pectin, a natural polysaccharide present in the cell walls of plants. To functionalize the fabric, pectin was firstly modified with glycidyl methacrylate (GMA) and then grafted on polyamide. Washing tests of treated fabrics showed the effectiveness of the treatment in reducing of about 90% the amount of microfibres released by untreated fabrics. Post-wash analysis of the treated fabrics revealed a promising resistance to the washing process.

Metabolic reprogramming is an important issue in tumor biology. An unexpected inter- and intra-tumor metabolic heterogeneity has been strictly correlated to tumor outcome. Tumor Necrosis Factor Receptor-Associated Protein 1 (TRAP1) is a molecular chaperone involved in the regulation of energetic metabolism in cancer cells. This protein is highly expressed in several cancers, such as glioblastoma, colon, breast, prostate and lung cancers and is often associated with drug resistance. However, TRAP1 is also downregulated in specific tumors, such as ovarian, bladder and renal cancers, where its lower expression is correlated with the worst prognoses and chemoresistance. TRAP1 is the only mitochondrial member of the Heat Shock Protein 90 (HSP90) family that directly interacts with respiratory complexes, contributing to their stability and activity but it is still unclear if such interactions lead to reduced or increased respiratory capacity. The role of TRAP1 is to enhance or suppress oxidative phosphorylation; the effects of such regulation on tumor development and progression are controversial. These observations encourage the study of the mechanisms responsible for the dualist role of TRAP1 as an oncogene or oncosuppressor in specific tumor types. In this review, TRAP1 puzzling functions were recapitulated with a special focus on the correlation between metabolic reprogramming and tumor outcome. We wanted to investigate whether metabolism-targeting drugs can efficiently interfere with tumor progression and whether they might be combined with chemotherapeutics or molecular-targeted agents to counteract drug resistance and reduce therapeutic failure.

Organic-inorganic halide perovskites, such as CH3NH3PbX3 (X = I(-), Br(-), Cl(-)), are attracting growing interest to prepare low-cost solar cells that are capable of converting sunlight to electricity at the highest efficiencies. Despite negligible effort on enhancing materials' purity or passivation of surfaces, high efficiencies have already been achieved. Here, we show that trap states at the perovskite surface generate charge accumulation and consequent recombination losses in working solar cells. We identify that undercoordinated iodine ions within the perovskite structure are responsible and make use of supramolecular halogen bond complexation to successfully passivate these sites. Following this strategy, we demonstrate solar cells with maximum power conversion efficiency of 15.7% and stable power output over 15% under constant 0.81 V forward bias in simulated full sunlight. The surface passivation introduces an important direction for future progress in perovskite solar cells.

Tumour cells have long been considered defective in mitochondrial respiration and mostly dependent on glycolytic metabolism. However, this assumption is currently challenged by several lines of evidence in a growing number of tumours. Ovarian cancer (OC) is one of the most lethal cancers worldwide, but it continues to be a poorly understood disease and its metabolic features are far to be elucidated. In this context, we investigated the role of tumour necrosis factor receptor-associated protein 1 (TRAP1), which is found upregulated in several cancer types and is a key modulator of tumour cell metabolism. Surprisingly, we found that TRAP1 expression inversely correlated with grade, stage and lower survival in a large cohort of OC patients. Accordingly, TRAP1 silencing induced resistance to cisplatin, resistant cells showed increased oxidative metabolism compared with their sensitive counterpart, and the bioenergetics cellular index of higher grade tumours indicated increased mitochondrial respiration. Strikingly, cisplatin resistance was reversible upon pharmacological inhibition of mitochondrial oxidative phosphorylation by metformin/oligomycin. At molecular level, increased oxidative metabolism in low TRAP1-expressing OC cells and tissues enhanced production of inflammatory mediators such as interleukin (IL)-6 and IL-8. Mechanistically, we identified members of the multidrug resistance complex (MDR) as key mediators of such metabolism-driven, inflammation-induced process. Indeed, treatment of OC cell lines with TNFα and IL6 induced a selective increase in the expression of TAP1 and multidrug resistance protein 1, whereas TAP1 silencing sensitized cells to cisplatin-induced apoptosis. Our results unveil a novel role for TRAP1 and oxidative metabolism in cancer progression and suggest the targeting of mitochondrial bioenergetics to increase cisplatin efficacy in human OC.Cell Death and Differentiation advance online publication, 20 May 2016; doi:10.1038/cdd.2016.39.

Interfaces between methylmethacrylate monomers, oligomers and silica nanoparticles (NPs) were explored by molecular dynamics simulations, infrared and solid state nuclear magnetic resonance spectroscopy. This knowledge allowed the control of the structure of the interfaces by employment of MMA macromonomers, and the design of an improved process for in situ polymerizations with a remarkable increase of NP dispersion.

Inspired by the powerful photosensitizing properties of the red hair pigments pheomelanins, a photoresponsive cysteine-containing variant of the adhesive biopolymer polydopamine (pDA) is developed via oxidative copolymerization of dopamine (DA) and 5-S-cysteinyldopamine (CDA) in variable ratios. Chemical and spectral analysis indicate the presence of benzothiazole/benzothiazine units akin to those of pheomelanins. p(DA/CDA) copolymers display impedance properties similar to those of biological materials and a marked photoimpedance response to light stimuli. The use of the p(DA/CDA) copolymer to implement a solution-processed hybrid photocapacitive/resistive metalinsulator- semiconductor (MIS) device disclosed herein is the fi rst example of technological exploitation of photoactive, red-hair-inspired biomaterials as soft enhancement layer for silicon in an optoelectronic device. The bio-inspired materials described herein may provide the active component of new hybrid photocapacitive sensors with a chemically tunable response to visible light.

Questa ricerca, basata su un’etnografia della durata di 9 mesi, indaga le pratiche lavorative quotidiane all’interno di un piccolo studio di lighting design. Il lavoro parte dalla convinzione che, per definire in cosa consista il lavoro, occorra indagare il contenuto effettivo del lavoro stesso, ossia le pratiche lavorative immerse nel loro contesto naturale, laddove esse avvengono. La pratica e le pratiche rappresentano una chiave di lettura dei diversi fenomeni sociali. Sul piano dell'ontologia sociale, le pratiche diventano l'oggetto costitutivo della società, come luogo di incontro delle diverse istanze oggettive e soggettive, micro e macro, strutturali e individuali, e dove queste stesse istanze si dissolvono. E, sul piano epistemologico, attraverso la lente delle pratiche, le stesse dicotomie oggetto/soggetto, struttura/azione, micro/macro vengono rigettate, nel tentativo di restituire la densità e la complessità della realtà sociale intesa come continuo prodotto endogeno delle pratiche stesse di attori concreti e reali, umani e non-umani. Per poter dare conto del lavoro di ricerca compiuto, ho scelto di iniziare accompagnando il lettore nel retroscena della ricerca stessa. Per questa ragione, nel primo capitolo racconto, nella forma di una storia naturale della ricerca, le scelte di ordine teorico e metodologico sottese al lavoro di ricerca. Descriverò come, a partire da un interrogativo di tipo teorico ed epistemologico sul concetto di pratica come strumento euristico e oggetto di ricerca, sono passato allo sviluppo delle domande di ricerca, all'individuazione del campo di indagine e alla definizione del piano empirico di ricerca. Nel secondo capitolo passo in rassegna i diversi modi in cui in sociologia è stato affrontato il tema delle pratiche. Da un lato, abbiamo autori classici, come Harold Garfinkel e in generale l'etnometodologia, Pierre Bourdieu, Anthony Giddens ed un filosofo come Theodore Schatzki; dall'altro un insieme di studi interdisciplinari di matrice organizzativa, che va sotto il nome di Practice-Based Studies, incentrati principalmente sugli aspetti cognitivi e materiali delle pratiche lavorative. I tre capitoli successivi sono dedicati al resoconto etnografico ed all'analisi delle pratiche lavorative di Studio Lambda. Nel terzo capitolo parlo degli spazi e dei tempi lavorativi di Studio Lambda, intesi non come sfondo all'azione dei soggetti, ma come essi stessi attori sociali. Nel quarto capitolo parlo delle diverse pratiche e micropratiche lavorative osservate all'interno di Studio Lambda, e che costituiscono il contenuto effettivo del lavoro dei lighting designers di Studio Lambda. Nel quinto capitolo vediamo quali sono i modi pratici attraverso cui i lighting designers costruiscono la propria identità professionale: I lighting designers protagonisti di questo resoconto etnografico sono degli artigiani della luce poiché trattano la luce nei suoi aspetti materiali e simbolici attraverso il dispiegamento quotidiano del proprio saper fare pratico. Nell'ultimo capitolo, infine, vengono tratte alcune conclusioni sul lighting design come un mondo sociale costituito da un insieme eterogeneo di attori umani e non-umani, in cui la luce e la progettazione illuminotecnica rappresentano un prodotto endogeno delle loro interazioni.

Rational approaches to engineering polydopamine fi lms with tailored properties for surface coating and functionalization are currently challenged by the lack of detailed information about the polymer structure and the mechanism of buildup. Using an integrated chemical and spectroscopic approach enables the demonstration of: a) a three-component structure of polydopamine, comprising uncyclized (catecholamine) and cyclized (indole) units, as well as novel pyrrolecarboxylic acid moieties; b) remarkable variations in the relative proportions of the cyclized and uncyclized units with starting dopamine concentration; c) the occurrence of oligomer components up to the tetramer level; d) the covalent incorporation of Tris buffer; and e) the role of dopamine quinone as a crucial control point for directing the buildup pathways and tuning the properties. The importance of the uncyclized amine-containing units in polydopamine adhesion is also highlighted. The proper selection of substrate concentration and buffer is thus proposed as a practical means of tailoring polydopamine functionality via control of competing pathways downstream of dopamine quinone.

Lithium salts have been shown to dramatically increase the conductivity in a broad range of polymeric and small molecule organic semiconductors (OSs). Here we demonstrate and identify the mechanism by which Li(+) p-dopes OSs in the presence of oxygen. After we established the lithium doping mechanism, we re-evaluate the role of lithium bis(trifluoromethylsulfonyl)-imide (Li-TFSI) in 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenyl-amine)9,9'-Spirobifluorene (Spiro-OMeTAD) based solid-state dye-sensitized solar cells (ss-DSSCs). The doping mechanism consumes Li(+) during the device operation, which poses a problem, since the lithium salt is required at the dye-sensitized heterojunction to enhance charge generation. This compromise highlights that new additives are required to maximize the performance and the long-term stability of ss-DSSCs.