Letteratura scientifica selezionata sul tema "Materiality matrices"

Using phenomenological descriptions, this essay explores the performative effects of disciplining our bodies to speak Standard American English as a second language and dialect. Theorizing the act of speaking as habituated embodiment in cultural matrices of power and hegemony, we foreground the sensuous materiality of the speaking body and interrogate how the enactive body works as a mnemonic device for normative ways of being. We contend the body is always more than a textual surface on which social meaning is discursively inscribed and reinforces the path toward a more phenomenologically materialist understanding of the body and embodiment in communication.

Sustainability reports seek to communicate the performance of organizations in the Environmental, Social and Governance (ESG) dimensions in line with the Sustainable Development Goals of the United Nations. Since there is no homogeneity of criteria among the various companies, even in the same sector, the several methodologies seeks to establish specific disclosure standards on ESG factors that facilitate communication between companies and investors about relevant and useful information for decisions through the identification of material and immaterial factors for each of the sectors. Information is material if its omission or misstatement influences people's decisions – likewise, information is immaterial if its omission or misstatement makes little or no difference to the decision-making process. In an ESG context, something is defined as material if it is reasonably likely to affect a company's financial condition or operating performance in terms of the impact it has on its value chain. There are two objectives of this study, first, to identify the main ESG factors that impact companies and that are at the heart of a resource-efficient sustainability strategy through the application of the materiality matrix, second, to envision that after this identification, the company it can optimize its strategic orientation and direct internal management in responding to material issues. This is a descriptive research with a qualitative approach, using bibliographical, normative and documental sources. The study made it possible to analyze and conclude on the importance of the correct diagnosis of material and immaterial factors in the elaboration of the materiality matrix in a banking institution with an impact on the value chain and on the real contribution to the objectives of sustainable development.

Materiality analysis is a multi-purpose tool for prioritising sustainability issues from the double perspective of companies and stakeholders, meaning that both parties contribute to identifying the present and emerging social and environmental risks and opportunities. The current study proposes a practical and structured approach for performing materiality analysis, integrating the well-known Global Reporting Initiative (GRI) materiality matrix and a new “adequacy matrix”. The purpose of the GRI materiality matrix is to prioritize sustainability issues in terms of relevance to both companies and stakeholders. The adequacy matrix supports evaluation of the transparency and effectiveness of corporate sustainability (CS) communication. Particularly, the paper aims to give indications to companies that want to prepare a sustainability report according to the GRI guidelines by planning the allocation of resources to reporting activities: the comparison between the positioning of GRI sustainability aspects in the two matrices serves in identifying the most critical issues for improving accountability. The proposed method includes a consistency test, to overcome the subjectivity, uncertainty and vagueness affecting judgements. The results provide managers with useful information for aligning CS strategic decision-making, sustainability reporting, and accountability to stakeholders. An illustrative application to a small and medium-sized (SME) company completes the paper.

Archaeologists often take stratigraphy for granted, using it for building chronologies, recognizing various natural and cultural formation processes, and understanding relations between features and settlements. But for the last few decades there has been a subtle shift in the way that we approach stratigraphy – in terms of both the kinds of techniques that can be applied (residue analyses, micromorphology, Harris matrices and so on) and the interpretive frameworks that can be employed. Perhaps it is not stratigraphy that we are talking about per se, but rather depositional practices – the many ways in which people make and alter archaeological deposits – in addition to the different interpretive frameworks that we apply to these physical accumulations.

After a long period of the inclusion of materiality matrices within standard setters documents and non-financial reports, the Global Reporting Initiative officially abandoned the materiality matrix in 2021 after the GRI 3 standard release. To bridge the detected gaps in the literature, this article aims to investigate approaches to and arguments for the matrix until the issuance of GRI 3. The two-step research strategy adopted gives the same level of attention to the opposite positions found. Phase 1 (approach-oriented) reviews the materiality matrix presentation in the 2014–2020 non-financial reports of a sample of worldwide sustainability-oriented companies. Phase 2 (argument-oriented) performs qualitative content analysis on feedback for the GRI 3 preparatory works. The findings show that, besides the staunch adopters, a core of non-adopters persisted and prevented the takeoff of the matrix. Moreover, further insights into possible drivers both in favour of and against these approaches are provided. The final discussion both considers the lessons learnt, overlapping with policy implications, and suggests future research avenues.

The industrial sector plays a vital role in economic development; therefore, there is a necessity to integrate sustainability into industrial development to maintain the economy and avoid any degradation impacts on the environment, and thereafter on society. Thus, do Bahraini companies have sustainability reports and if so, are these reports based on GRI guidelines? Has the status of their sustainability reports been analyzed? This research aims to examine the sustainability reports of companies by analyzing the status of sustainability aspects in their materiality matrices to assist in identifying and prioritizing the most significant sustainability issues for advancement in their future reporting and to improve their environmental performance. This study employs a content analysis approach and analyzes 11 reports from the period 2016–2020 for three companies in Bahrain’s large industrial sector. The study reveals that the companies using materiality analysis in their reporting benefit from better monitoring and measuring of their environmental performance, and from implementing SDGs. Furthermore, the study indicates that the utilization of a materiality matrix as a reporting tool can define and improve report contents by considering stakeholders’ views, consequently, improving the quality of the sustainability reports. The study concludes by proposing a set of recommendations.

Purpose Nowadays, in this highly dynamic and complex context, companies have to act in a socially responsible and sustainable way to survive, creating shared value. The purpose of this paper is to analyse, through descriptive statistics, the elements that Italian banks identify as strategic to increasing their relational and reputational capital and to being in consonance with stakeholder’s expectations. Design/methodology/approach This paper investigates the width (number of intermediaries that included the materiality matrix in their non-financial reports) and the depth (number of indicators in the matrix) of the phenomenon to detect the bank’s attention on critical topics for their stakeholders. Findings The focus is on materiality matrices in order to detect a correspondence among the significant indicators selected by the banks and those value generators for stakeholders. In the perspective used in this work, property is also a stakeholder; indeed, wanting to use the terminology of the viable systems approach, property represents a relevant supra-system as it is critical and influential for the decision makers. Research limitations/implications The main limits are the low number of non-financial reports published by Italian banks, and the little information on the type of stakeholder involved in the building of the materiality matrix. Originality/value The originality of this work is multifaceted. Primarily, there are no similar studies in the banking sector. The present work intends to go beyond the studies already in the literature on mapping and stakeholder prioritisation as well as on the identification and selection of material themes. Moreover, having found, during the analysis of the banks’ reports, the heterogeneity of indicators identified as material, for both banks and stakeholders, the same have been traced back to the related stages identified by Carroll in the pyramid of social responsibility.

In advanced globalization, the digital code, computer, and Internet become tools of cultural change. 2-3-4.0 generation media produce images, artificial events, objects, as well as methods of vision prevailing in design, design processes, and communication. The number of visibility types offered to users, results in media matrices becoming regimes of (for) the eye, of (for) a bodily experience. It also shapes a sense of reality by means of media space (TV stream, cyberspace) and spaces inscribed in media forms (simulations, hybrids, onto-ontological topias). Two issues seem of particular relevance here. Questions about access to reality offered by ‘images’ (satellites, HDMI helmets, combat glasses, etc.) and possibilities of seeing the world from behind the visual media matrices. Media, multi-media communication platforms distribute not only schemes of viewing, but also the right to look (extranet, friends lists, access to archives and libraries, consumer profiles collected by Google, MS, etc.). The excess of artificial forms and spaces, on the other hand, directs attention to participation and participants of culture: individuals and communities (real, imagined, virtual). Their activities in cyberspace, including identity and identity practices, should be the focus of interest. The author of the text reflects upon identity practices of the Praktykować media/Praktykować siebie individual, that is the individual’s participation in culture through the prism of immaterial materiality, self-care, and the need for bonds and integration with the Others. She discusses techniques of advanced audio-vision (their matrices and spatiality), as well as creation of subjective coherence negotiated with others in terms of individual – group (conventional) – universal content (e.g. humanity). Identity practices are located within the framework of data flows and transmissions, information bubbles, heterotopia, and identities of legitimization, resistance, and design implemented there. The author of the text also perceives identity from the perspective of a person and a mask, of users’ tactics articulating their presence in cyber-virtual communities (e.g. avatars, nicks, multiple identities), as well as in the perspective of data visualization: user profiles, metric identifiers, files, selection algorithms, search history, archives of published photos…, in other words – institutional (cyber)surveillance strategies.

This article analyses the construction of the ‘other’ in photographs of the Portuguese Colonial War and its relation with the traumatic memory of the conflict and coloniality itself. Political and cultural dimensions associated with this particular context of the relation with the ‘other’ – interracial violence, the ideological frame of the Portuguese colonial regime influenced by Luso-tropicalism, and the experience of these contradictions in a war situation – constitute traumatic memories that have been made silent and socially invisible after the transition to a democratic and non-colonialist regime. This article wishes to critically revisit images kept in private collections owned by Portuguese soldiers, where the ‘other’ is represented as the violent and primitive enemy as well as the gentle colonized ally and object of the social action of the troops. It intends to explore the conditions of production of those photographs, their performative materiality, their political use at the time, and the cultural matrices that frame them. The article is grounded in the idea of photography as mediator of postmemory, fundamental for the negotiation of meanings and the cultural integration of the trauma related to the colonial experience and its ambiguities, into the individual and collective representation of the war.

Cette thèse approfondit le concept de matérialité extra-financière, peu abordé dans la littérature académique, et l’artefact de matrices, socle des publications des informations extra-financières. Cette notion étant empreinte de définitions polysémiques et de référentiels aux lignes directrices nébuleuses, les pratiques actuelles des entreprises manquent de rigueur engendrant des problèmes de transparence et de comparabilité pour les parties prenantes.Aussi, à travers les cadres théoriques de la Théorie Néo-Institutionnelle et de Simons (1995) nous explorons ce concept. Les mécanismes de contrôles mobilisés dans une visée stratégique, en particulier l’interactif et le diagnostique, nous permettent de proposer un modèle de mesure tridimensionnel d’analyse. Il apporte un aspect dynamique à l’évaluation de matérialité en prenant en compte certes les attentes, mais aussi les perceptions et la tendance des parties prenantes. Ce dernier est testé auprès de 10 000 parties prenantes internes et externes dans un contexte de banque coopérative, en particulier la Banque Populaire Alsace Lorraine Champagne. La spécificité de ce terrain de recherche nous amène également à approfondir la notion d’ubiquité et à inclure d’autres parties prenantes que les sociétaires historiquement considérées en tant que tel. Nos résultats mettent en lumière plusieurs apports majeurs comme une innovation processuelle rigoureuse avec des étapes permettant d’élaborer l’artefact des matrices, l’analyse des données statistiques créatrices et porteuses de sens afin de piloter la stratégie de Responsabilité Globale d’une organisation, une typologie des pratiques de matérialité dans les banques coopératives et actionnariales, une typologie des enjeux et le dévoiement des échelles sur l’outil produisant des illusions de consensus
This thesis takes a closer look at the concept of extra-financial materiality, which has received little attention in the academic literature, and the artefact of matrices, the basis for the publication of extra-financial information. As this concept is marked by polysemous definitions and nebulous guidelines, companies' current practices lack rigour, leading to problems of transparency and comparability for stakeholders.Using the theoretical frameworks of Neo-Institutional Theory and Simons (1995), we explore this concept. The control mechanisms mobilised for strategic purposes, in particular the interactive and diagnostic ones, enable us to propose a three-dimensional measurement model for analysis. It adds a dynamic aspect to the assessment of materiality by taking into account not only expectations, but also the perceptions and trends of stakeholders. The model is being tested with 10,000 internal and external stakeholders in the context of a cooperative bank, in particular Banque Populaire Alsace Lorraine The specific nature of this field of research has also led us to explore the notion of ubiquity in greater depth and to include stakeholders other than the members historically considered as such. Our results highlight a number of major contributions, including a rigorous process innovation with stages enabling the matrices artefact to be developed, the analysis of statistical data that creates and conveys meaning in order to steer an organisation's Global Responsibility strategy, a typology of materiality practices in cooperative and shareholder banks, a typology of issues and the misuse of scales on the tool producing illusions of consensus

L’attività di ricerca svolta è stata focalizzata sullo studio e la realizzazione di Materiali Autodiagnosticanti: ovvero materiali con la duplice funzione strutturale e di sensore. I materiali scelti per questo scopo sono compositi a matrice polimerica, dato il loro vasto campo applicativo e la loro grande versatilità. Il materiale realizzato consta di due parti fondamentali: il rinforzo strutturale costituito da fibre di vetro in resina epossidica e l’elemento sensibile costituito da una fase elettricamente conduttrice in carbonio in forma di fibre lunghe unidirezionali o nanoparticelle o nanofibre disperse nella resina epossidica. I compositi ibridi, realizzati in forma di tondini mediante un processo di pultrusione manuale, sono costituiti dall’elemento sensibile interno coassialmente rivestito di vetroresina. In tutti i casi l’efficienza dell’autodiagnosi è stata valutata correlando la variazione di resistenza elettrica della fase conduttrice con il carico e/o la deformazione applicati all’intero composito. Per ciascun tipo di elemento sensibile sono stati indagati aspetti precisi: 1. nel caso degli elementi sensibili in fibra di carbonio unidirezionali ci si è particolarmente soffermati sull’influenza della quantità di vetro esterna sulle proprietà di autodiagnosi; 2. nei provini con elementi sensibili realizzati con nano-particelle e nanofibre di carbonio in resina epossidica si è indagato l’effetto della tipologia di particelle impiegate (area superficiale, dimensione, aspect ratio, ecc.) sulle proprietà di conducibilità elettrica e di autodiagnosi. I risultati dei sensori con fibra di carbonio hanno evidenziato che questo tipo di materiale non è particolarmente adatto ad una funzione di monitoraggio continuo della sollecitazione, bensì ha interessanti applicazioni quale “sensore di guardia” con comportamento tipo “on-off”. Ciò a causa del particolare meccanismo di conduzione che consente sempre un cospicuo passaggio di corrente fino alla rottura delle fibre di carbonio. La ricerca ha evidenziato che tale comportamento di guardia può essere influenzato dalla quantità di vetro che riveste l’elemento sensibile. In particolare, l’attivazione del segnale di guardia (resistenza elettrica pari ad infinito) può essere anticipato rispetto alla rottura finale del composito aumentando la quantità di vetro. I sensori realizzati con nanoparticelle di carbonio hanno invece mostrato grande capacità di monitoraggio in continuo, e ciò a causa del fatto che in questi sistemi la conducibilità elettrica è associata ad un modello percolativo. All’aumentare del carico (e quindi della deformazione) del materiale, le particelle conduttrici vengono progressivamente allontanate le une dalle altre consentendo di registrare un graduale e continuo aumento della resistenza elettrica. In questi sistemi, tuttavia, la natura, morfologia, dimensione, area superficiale, ecc. delle nano-particelle influenzando notevolmente la formazione del network percolativo, influenzano conseguentemente anche le proprietà di autodiagnosi. Le particelle ad elevata area superficiale hanno mostrato le migliori proprietà di autodiagnosi. Nel passaggio dalle nanoparticelle alle nano-fibre di carbonio non ha portato i miglioramenti attesti. Questo particolare sistema è stato indagato in quanto consente teoricamente di ottenere buona conducibilità elettrica con minore quantitativo di carica grazie all’elevato aspect ratio delle nanofibre, tuttavia la manifattura degli elementi sensibili è risultata estremamente complessa. Le nanofibre commerciali, infatti, vengono fornite in forma di aggregati micrometrici e che necessitano lunghe manipolazioni con solventi per essere disaggregati. Tali operazioni, possibili con limitate quantità di materiale, sono invece molto difficoltose e delicate quando applicate a sistemi più grandi quali la pultrusione impiegata per realizzare i materiali di questa sperimentazione. I sensori ottenuti in nano fibra di carbonio, frutto di un compromesso tra il livello di dispersione delle nanofibre nella resina e la processabilità, hanno dimostrando proprietà di autodiagnosi molto simili a quelle delle particelle di carbonio con area superficiale bassa, assai poco soddisfacenti. I materiali risultati più idonei alle funzioni di autodiagnosi, ovvero quelli con elemento sensibile in nanoparticelle di carbonio ad elevata area superficiale, sono stati poi provati in condizioni pratiche di esercizio, quali rinforzi strutturali in travi di calcestruzzo. I risultati hanno mostrato che i materiali realizzati conservano le proprietà di autodiagnosi sotto carico anche se inseriti in sistemi massivi come il calcestruzzo e che, inoltre, grazie alla loro sensibilità è stato possibile monitorarne anche la fase di presa ed indurimento.
The research carried out was focused on the study and production of Composite Smart Material: materials with the dual function: structural and sensor. The materials chosen for this purpose are polymer matrix composites, due to their vast application field and their versatility. The material produced consists of two basic parts: the structural reinforcement consists of glass fibers in epoxy resin and the sensible element consists of a phase-sensitive electrically conductive carbon in the form of unidirectional long fibers or nanoparticles or nanofibers dispersed in epoxy resin. The hybrid composite, realized in the form of rods by a process of pultrusion manual, consisting of the element sensitive internal coaxially coated fiberglass. In all cases the efficiency of smart properties was assessed by correlating the change in electrical resistance of the phase conductor with the load and / or deformation applied to the entire composite. For each type of sensor element have been investigated specific aspects: 1. in the case of sensitive elements in carbon fiber unidirectional one is particularly dwelt on the influence of the amount of exterior glass on the properties of self-diagnosis; 2. in samples with sensitive elements made of nano-particles and carbon nanofibers in epoxy resin was investigated the effect of the type of particles used (surface area, size, aspect ratio, etc..) on the properties of electrical conductivity and self-diagnosis. The results of the sensors with carbon fiber have shown that this type of material is not particularly suitable for continuous monitoring function of the stress, but has interesting applications such as "Sensor Guard" behavior such as "on-off". This is because of the particular mechanism that allows always run a large current passing through rupture of carbon fibers. Research has shown that this behavior may be influenced guard by the amount of glass that covers the sensing element. In particular, the activation of the signal call (electrical resistance equal to infinity) may be faster than the final break of the composite by increasing the amount of glass. The sensors made of carbon nanoparticles have shown great ability but continuous monitoring owing to the fact that in these systems, the electrical conductivity is associated with a percolation model. Increasing load (ie deformation) of the material, the conductive particles are gradually removed from each other allowing you to record a gradual and continuous increase in electrical resistance. In these systems, however, the nature, morphology, size, surface area, etc.. of nano-particles significantly influence the formation of the percolation network, thus also affecting the properties of self-diagnosis. Particles with high surface area showed the best properties of self-diagnosis. In the transition from nanoparticles to nano-carbon fibers did not lead to improvements attests. This particular system has been investigated theoretically since it allows to obtain good electrical conductivity with less quantity of charge thanks to the high aspect ratio of nanofibers, but the manufacturing of the sensing elements was extremely complex. The nanofibers trade, in fact, is provided in the form of aggregated micro and requiring lengthy manipulations with solvents to be broken. Such operations, possibly with small amounts of material, are very difficult and sensitive when applied to larger systems such as pultrusion designed to produce the materials of this trial. The sensors obtained in nano carbon fiber, a compromise between the degree of dispersion of nanofibers in the resin and processability, showed properties very similar to the self of carbon particles with low surface area, not very satisfactory. The materials are more appropriate to the functions of self-diagnosis or those with sensitive element in nanoparticles of carbon with high surface area, were then tested in practical conditions of operation, such as structural reinforcement in concrete beams. The results showed that the materials remain the property of self-made load even if incorporated into systems such as the massive concrete and that, furthermore, due to their sensitivity has been possible to also monitor the stage setting and hardening.

In the field of Tissue Engineering, a new concept has been developed in the last few years. The formation of new tissue induced by a tissue engineered system needs to be accompanied by the achievement of a complete tissue functionality and scaffold properties have to be designed following the principles of biomimetics, i.e. the complexity of the physiological environment has to be translated and reproduced in the cell-scaffold construct. This approach is especially challenging when the interface between two tissues has to be restored. In this case, the scaffold has not only to sustain the regeneration of two different tissues, but also to ensure the regeneration of a functional interfacial zone between them. Therefore, scaffold properties must reflect the complexity of tissue boundary structures, in terms of controlled gradients in morphological, chemical and mechanical properties. The aim of this research work was the application of these advanced principles to the regeneration of the osteochondral defect, which is a degenerative pathology involving both cartilage and bone tissue, whose current treatments are uneffective in the long term. In this work, a multiphasic scaffold for osteochondral Tissue Engineering was produced and characterized. Silk fibroin-based 3D sponges were employed for the chondral and subchondral components for cartilage and bone regeneration, respectively, to exploit the biocompatibility and versatility of silk fibroin in Tissue Engineering applications. For the restoration of a functional interface, a nanometric net was used to separate the two components, in order to allow a dialogue among cells between the two phases thanks to a physiological solute flow, while preventing cell migration towards the chondral site, especially of blood cells which may cause mineralization of the non-calcified cartilage. For the chondral component, two different strategies were explored. First, pure silk fibroin sponges produced by salt leaching were combined to static or dynamic culture conditions to evaluate the chondrogenic potential of adipose- derived stem cells (ASCs). These cells have indeed many advantages for cartilage Tissue Engineering applications, such as abundance, easy accessibility, ability of self-renewal and stability during in vitro culture. The best differentiation of ASCs towards chondrocytes was achieved after 28 days of culture in a static environment and chondrogenic media, in terms of higher chondrogenic gene expression, new cartilage extracellular matrix deposition and increase of compressive mechanical properties. ASC/scaffold constructs were then implanted in vivo in a rat xiphoid critical size defect for 8 weeks and also in this case, the best outcomes in terms of new tissue volume and quality were obtained when static conditions and chondrogenic medium were employed during pre-culture. The aim of the second strategy presented in this work was to modify silk fibroin (SF) sponges with the addition of hyaluronic acid (HA). Besides hyaluronic acid is a natural component of cartilage and contributes to its biomechanics thanks to its ability to retain a remarkable amount of water, it has been shown to modulate chondrocyte phenotype when employed in scaf- folds for cartilage regeneration. Therefore, we exploited its properties producing silk fibroin/hyaluronic acid scaffolds by salt leaching at different HA concentrations, eventually cross-linked by genipin to improve HA retention. SF/HA sponges were completely characterized in terms of physical, chemical and mechanical properties and then used to culture primary chondrocytes in vitro. Results demonstrated that the scaffolds with the highest amount of hyaluronic acid both with and without cross-linking elicited better responses in cartilage cells with respect to pure silk fibroin sponges, in terms of chondrogenic phenotype enhancement and new cartilage extracellular matrix deposition. The nanometric net of the multicomponent scaffold for osteochondral regeneration was produced by electrospinning of poly-d,l-lactid acid/polyethylene glycol (PdlLA/PEG) blends. PdlLA was employed since it is a well-known biocompatible polymer and it is easy to process with this technique, while PEG was added to avoid fiber shrinkage in an aqueous environment. Nets were characterized in terms of morphology and thermal properties, then assembled to a silk fibroin sponge without any modification to their geometry. To preliminarily evaluate the biological properties of PdlLA/PEG electrospun nets, a system to co-culture chondrocytes on scaffolds with net and osteoblasts was designed and validated, so that the biochemical communications between cells could take place through the net fibers. In the future, this system will be employed to evaluate how osteoblasts can improve chondrocyte response in terms of phenotype maintenance and new cartilage tissue deposition. The results reported in this research work will be the basis for the final design of a multicomponent scaffold which comprises the best outcomes obtained. Hence, SF/HA scaffolds which elicited the best responses on chondrocytes will be used in combination with ASCs, in order to verify their potential to sus- tain chondrogenesis in vitro. Then, they will be assembled to the nanometric net and, before moving to an appropriate in vivo study, the co-culture system will be employed to assess how the cellular dialogue with osteoblasts can have beneficial effects on the chondrogenic differentiation of adipose-derived stem cells.

In the field of Tissue Engineering, a new concept has been developed in the last few years. The formation of new tissue induced by a tissue engineered system needs to be accompanied by the achievement of a complete tissue functionality and scaffold properties have to be designed following the principles of biomimetics, i.e. the complexity of the physiological environment has to be translated and reproduced in the cell-scaffold construct. This approach is especially challenging when the interface between two tissues has to be restored. In this case, the scaffold has not only to sustain the regeneration of two different tissues, but also to ensure the regeneration of a functional interfacial zone between them. Therefore, scaffold properties must reflect the complexity of tissue boundary structures, in terms of controlled gradients in morphological, chemical and mechanical properties. The aim of this research work was the application of these advanced principles to the regeneration of the osteochondral defect, which is a degenerative pathology involving both cartilage and bone tissue, whose current treatments are uneffective in the long term. In this work, a multiphasic scaffold for osteochondral Tissue Engineering was produced and characterized. Silk fibroin-based 3D sponges were employed for the chondral and subchondral components for cartilage and bone regeneration, respectively, to exploit the biocompatibility and versatility of silk fibroin in Tissue Engineering applications. For the restoration of a functional interface, a nanometric net was used to separate the two components, in order to allow a dialogue among cells between the two phases thanks to a physiological solute flow, while preventing cell migration towards the chondral site, especially of blood cells which may cause mineralization of the non-calcified cartilage. For the chondral component, two different strategies were explored. First, pure silk fibroin sponges produced by salt leaching were combined to static or dynamic culture conditions to evaluate the chondrogenic potential of adipose- derived stem cells (ASCs). These cells have indeed many advantages for cartilage Tissue Engineering applications, such as abundance, easy accessibility, ability of self-renewal and stability during in vitro culture. The best differentiation of ASCs towards chondrocytes was achieved after 28 days of culture in a static environment and chondrogenic media, in terms of higher chondrogenic gene expression, new cartilage extracellular matrix deposition and increase of compressive mechanical properties. ASC/scaffold constructs were then implanted in vivo in a rat xiphoid critical size defect for 8 weeks and also in this case, the best outcomes in terms of new tissue volume and quality were obtained when static conditions and chondrogenic medium were employed during pre-culture. The aim of the second strategy presented in this work was to modify silk fibroin (SF) sponges with the addition of hyaluronic acid (HA). Besides hyaluronic acid is a natural component of cartilage and contributes to its biomechanics thanks to its ability to retain a remarkable amount of water, it has been shown to modulate chondrocyte phenotype when employed in scaf- folds for cartilage regeneration. Therefore, we exploited its properties producing silk fibroin/hyaluronic acid scaffolds by salt leaching at different HA concentrations, eventually cross-linked by genipin to improve HA retention. SF/HA sponges were completely characterized in terms of physical, chemical and mechanical properties and then used to culture primary chondrocytes in vitro. Results demonstrated that the scaffolds with the highest amount of hyaluronic acid both with and without cross-linking elicited better responses in cartilage cells with respect to pure silk fibroin sponges, in terms of chondrogenic phenotype enhancement and new cartilage extracellular matrix deposition. The nanometric net of the multicomponent scaffold for osteochondral regeneration was produced by electrospinning of poly-d,l-lactid acid/polyethylene glycol (PdlLA/PEG) blends. PdlLA was employed since it is a well-known biocompatible polymer and it is easy to process with this technique, while PEG was added to avoid fiber shrinkage in an aqueous environment. Nets were characterized in terms of morphology and thermal properties, then assembled to a silk fibroin sponge without any modification to their geometry. To preliminarily evaluate the biological properties of PdlLA/PEG electrospun nets, a system to co-culture chondrocytes on scaffolds with net and osteoblasts was designed and validated, so that the biochemical communications between cells could take place through the net fibers. In the future, this system will be employed to evaluate how osteoblasts can improve chondrocyte response in terms of phenotype maintenance and new cartilage tissue deposition. The results reported in this research work will be the basis for the final design of a multicomponent scaffold which comprises the best outcomes obtained. Hence, SF/HA scaffolds which elicited the best responses on chondrocytes will be used in combination with ASCs, in order to verify their potential to sus- tain chondrogenesis in vitro. Then, they will be assembled to the nanometric net and, before moving to an appropriate in vivo study, the co-culture system will be employed to assess how the cellular dialogue with osteoblasts can have beneficial effects on the chondrogenic differentiation of adipose-derived stem cells.

L’utilizzo degli FRP (Fiber Reinforced Polymer) nel campo dell’ingegneria civile riguarda essenzialmente il settore del restauro delle strutture degradate o danneggiate e quello dell’adeguamento statico delle strutture edificate in zona sismica; in questi settori è evidente la difficoltà operativa alla quale si va in contro se si volessero utilizzare tecniche di intervento che sfruttano materiali tradizionali. I motivi per cui è opportuno intervenire con sistemi compositi fibrosi sono: • l’estrema leggerezza del rinforzo, da cui ne deriva un incremento pressoché nullo delle masse sismiche ed allo stesso tempo un considerevole aumento della duttilità strutturale; • messa in opera senza l’ausilio di particolari attrezzature da un numero limitato di operatori, da cui un minore costo della mano d’opera; • posizionamento in tempi brevi e spesso senza interrompere l’esercizio della struttura. Il parametro principale che definisce le caratteristiche di un rinforzo fibroso non è la resistenza a trazione, che risulta essere ben al di sopra dei tassi di lavoro cui sono soggette le fibre, bensì il modulo elastico, di fatti, più tale valore è elevato maggiore sarà il contributo irrigidente che il rinforzo potrà fornire all’elemento strutturale sul quale è applicato. Generalmente per il rinforzo di strutture in c.a. si preferiscono fibre sia con resistenza a trazione medio-alta (>2000 MPa) che con modulo elastico medio-alto (E=170-250 GPa), mentre per il recupero degli edifici in muratura o con struttura in legno si scelgono fibre con modulo di elasticità più basso (E≤80 GPa) tipo quelle aramidiche che meglio si accordano con la rigidezza propria del supporto rinforzato. In questo contesto, ormai ampliamente ben disposto nei confronti dei compositi, si affacciano ora nuove generazioni di rinforzi. A gli ormai “classici” FRP, realizzati con fibre di carbonio o fibre di vetro accoppiate a matrici organiche (resine epossidiche), si affiancano gli FRCM (Fiber Reinforced Cementitious Matrix), i TRM (Textile Reinforced Mortars) e gli SRG (Steel Reinforced Grout) che sfruttano sia le eccezionali proprietà di fibre di nuova concezione come quelle in PBO (Poliparafenilenbenzobisoxazolo), sia un materiale come l’acciaio, che, per quanto comune nel campo dell’edilizia, viene caratterizzato da lavorazioni innovative che ne migliorano le prestazioni meccaniche. Tutte queste nuove tipologie di compositi, nonostante siano state annoverate con nomenclature così differenti, sono però accomunate dell’elemento che ne permette il funzionamento e l’adesione al supporto: la matrice cementizia

L’additive manufacturing è uno dei temi principali della quarta rivoluzione industriale; definita come Industry 4.0. L'uso del calcestruzzo nelle tecnologie additive è molto promettente e consente lo sviluppo di applicazioni innovative nel settore delle costruzioni; per l’architettura; nel campo del design ed in quello industriale. Le tecniche di additive manufacturing of concrete offrono numerosi vantaggi: riduzione dei tempi e dei costi di produzione, maggiore personalizzazione e libertà nella progettazione, minore spreco di materiale e minori emissioni inquinanti, maggiore sicurezza sul lavoro. Nel presente lavoro è stata effettuata una revisione delle tecniche esistenti e dei vantaggi legati a questo tipo di produzione e sono state descritte le caratteristiche richieste al calcestruzzo affinché possa risultare estrudibile con lo scopo di sviluppare materiali innovativi a base cementizia estrudibili con proprietà funzionali avanzate. Sono state ottimizzate delle miscele a base cementizia stampabili con ottime proprietà meccaniche, contenenti aggregati di riciclo e resistenti alle alte temperature. Il processo di stampa del calcestruzzo utilizza una tecnica di produzione additiva, basata su strati per costruire forme geometriche complesse senza cassaforma e presenta quindi un vantaggio unico rispetto ai convenzionali metodi di costruzione. Le proprietà indurite delle formulazioni e gli effetti del processo di stratificazione su densità, resistenze meccaniche e ritiro igrometrico sono presentati insieme alle implicazioni relative alle proporzioni della miscela. Il lavoro sperimentale dimostrerà il potenziale della stampa del calcestruzzo come nuovo processo produttivo praticabile che può introdurre una maggiore libertà geometrica nel processo di progettazione, oltre a offrire un nuovo mezzo di produzione che potrebbe evitare la necessità di produrre in serie elementi identici in calcestruzzo con un numero limitato di varianti.
Additive manufacturing is one of the main topics of the fourth industrial revolution; defined as Industry 4.0. Usage of concrete in additive technologies allows the development of innovative applications in the construction sector; for architecture; in the design field and in the industrial one. Additive manufacturing of concrete techniques offer several advantages: reduction of production time and costs; greater customization and design freedom; less material waste and less polluting emissions, higher level of job security. In the present work, a rewiew of existing techniques, of vantages related to this kind of production has been done and the characteristics required to concrete to be extruded are described in order to develop innovative extrudable cement-based materials with advanced functional properties. Cement-based printing mixtures with outstanding mechanical properties, containing recycled aggregates and resistant to high temperatures have been developed. The concrete printing process uses an additive, layer-based, manufacturing technique to build complex geometrical shapes without formwork and thus has a unique advantage over conventional construction methods. The hardened properties of the formulations and the effects of the layering process on density, mechanical strengths and drying shrinkage are presented together with the implication for mix proportions. The experimental work will demonstrate the potential of concrete printing as a viable new production process that can introduce greater geometric freedom into the design process as well as offering a novel means of manufacture that could avoid the need to mass produce identical concrete parts with limited numbers of variants.

This work focuses on the inclusion of montmorillonite(MMT) and reduced graphene oxide (2D nanomaterials) in polyamide-imide(PAI) matrices. The challenge was to find specific methods to obtain a polymer nanocomposite with better and/or alternatives features compared to the standard polymer. PAI in general exhibits properties which can be attributed to the class of high-performance enamels. The effect of the nanomaterial inclusions on chemical resistance, thermal, mechanical and electric properties was investigated after a specific industrial application: magnet wire coating. For this purpose, nanocomposites were coated on the surface of copper wires and cured to form an electrical insulation film. In literature, several methods for a variety of polymer systems were widely investigated, except for PAI, on which there has been little research. Furthermore, the use of nanomaterials in polymeric matrices for copper wire applications still remains an unexplored field. In order to obtain polymer nanocomposite, two different methods have been used in this work: the solvent casting method and in situ polymerization. After the characterization of the 2D nanomaterials and the polymer, the first part of this thesis dealt with the nanocomposites synthesis of PAI-MMT modified with cationic surfactants of alkylammonium type [benzyl (hydrogenated tallow alkyl) dimethyl ammonium]. Surfactants provide an organophilic character to the silicates through a surface functionalization able to provide a good interaction with hydrophobic polymers. The introduction of groups characterized by a greater steric hindrance also has the advantage of spacing the platelets, facilitating the subsequent incorporation of the macromolecules. The physical separation of the silicate layers is an aspect of extreme importance, since only when completely exfoliated, nanocomposite can offer all its peculiar properties. In situ polymerization was performed by swelling MMT intergalleries with trimellitic anhydride (TMA) monomers followed by addition of MDI and subsequent polymerization to PAI within the intergalleries. The solvent casting method is based on swelling MMT intergalleries with solvent where the polymer is soluble (NMP in this case). Mixing of polymer and layered nanomaterial solutions results in intercalation of polymer chains and displacement of the solvent within the interlayers of silicates. With the approach of in situ polymerization, a new level of exfoliated particle concentration could be reached but in comparison, the solvent casting method turned out to be simpler and faster. In the second part of this work, reduced graphene oxide (rGO) was used instead of organoclay. The two methods previously described were also used for the synthesis of rGO-PAI nanocomposites. With in situ polymerization, a novel approach toward PAI-PE-rGO hybrid system (where PE indicates polyester) was developed. For this purpose, first rGO was covalently linked to the polyester (through the reaction with a dialcohol and a diacid in a 1:2 ratio, obtaining a polyester with terminal acid groups), then the PAI component was synthesized using these groups for the amide formation by reaction with MDI (methylenediphenyldiisocyanate). The success of covalent linking between rGO and polymer matrix was confirmed by the analysis of the acid number using the potentiometric method and FTIR. The MMT-PAI and rGO-PAI resins were then applied to the copper wire on which the control tests were performed. The last part of this dissertation focused on the synthesis of PAI-rGO nanocomposites (by solvent casting method) at different concentrations in order to obtain a light conductive resin. Even if a typical property of this kind of polymer is a good electrical insulation, it could be useful, for some applications, obtaining conductive properties. Subsequently, the varnishes were applied by means of a film applicator on tin-plate sheets and observed through an optical microscope and SEM.

Il progetto alla base della presente tesi di laurea, sviluppato presso la Dow Italia di Correggio (RE), riguarda lo studio di formulazioni di materiali compositi con matrice polimerica a base di isocianurato, al fine di preparare manufatti con migliorato comportamento in condizioni d’incendio. In particolare si cerca di migliorare il parametro di tenuta isolamento nei test di resistenza al fuoco di serramenti. In bibliografia sono presenti numerosi esempi di matrici polimeriche usate per lo sviluppo di questi materiali, principalmente a base di silicio, mentre la matrice organica che è stata utilizzata in questo progetto è a base di poliisocianurato (PIR) rigido, scelto per la sua elevata stabilità termica. Sono stati analizzati nel dettaglio i vari approcci che sono stati affrontati al fine d’individuare la formulazione più adeguata per lo scopo che ci si è prefissati.

Durante l'attività di ricerca sono stati sviluppati tre progetti legati allo sviluppo e ottimizzazione di materiali compositi. In particolare, il primo anno, siamo andati a produrre materiali ceramici ultrarefrattari tenacizzati con fibre di carburo di silicio, riuscendo a migliorare il ciclo produttivo e ottenendo un materiale ottimizzato. Durante il secondo anno di attività ci siamo concentrati nello sviluppo di resine epossidiche rinforzate con particelle di elastomeri florurati che rappresentano un nuovo materiale non presente nel mercato utile per applicazioni meccaniche e navali. L'ultimo anno di ricerca è stato svolto presso il laboratorio materiali di Ansaldo Energia dove è stato studiato il comportamenteo di materiali per turbine a gas.
During the PhD were developed three projects related to the development and optimization of composite materials. In particular, the first year, we went to produce ceramic materials for refractory application, toughened with fibers of silicon carbide, managing to improve the production cycle and to obtain an optimized material. During the second year of operation, we have focused in the development of epoxy resins reinforced with particles of Fluorinated elastomers, that represent a new material not found in the market useful for mechanical and naval application. The last year of research has been done in the Materials laboratory of Ansaldo Energia were has been studied materials for gas turbines and their application.

Durante l'attività di ricerca sono stati sviluppati tre progetti legati allo sviluppo e ottimizzazione di materiali compositi. In particolare, il primo anno, siamo andati a produrre materiali ceramici ultrarefrattari tenacizzati con fibre di carburo di silicio, riuscendo a migliorare il ciclo produttivo e ottenendo un materiale ottimizzato. Durante il secondo anno di attività ci siamo concentrati nello sviluppo di resine epossidiche rinforzate con particelle di elastomeri florurati che rappresentano un nuovo materiale non presente nel mercato utile per applicazioni meccaniche e navali. L'ultimo anno di ricerca è stato svolto presso il laboratorio materiali di Ansaldo Energia dove è stato studiato il comportamenteo di materiali per turbine a gas.
During the PhD were developed three projects related to the development and optimization of composite materials. In particular, the first year, we went to produce ceramic materials for refractory application, toughened with fibers of silicon carbide, managing to improve the production cycle and to obtain an optimized material. During the second year of operation, we have focused in the development of epoxy resins reinforced with particles of Fluorinated elastomers, that represent a new material not found in the market useful for mechanical and naval application. The last year of research has been done in the Materials laboratory of Ansaldo Energia were has been studied materials for gas turbines and their application.

Postcolonial feminism in international relations (PFIR) is a disciplinary field devoted to the study of world politics as a site of power relations shaped by colonization. PFIR combines postcolonial and feminist insights to explore questions such as how the stratum of elite power intersects with subterranean layers of colonization to produce our contemporary world politics; how these interrelationships between race, gender, sex, and class inform matrices of power in world politics; and how we account for elite and subaltern agency and resistance to the hegemonic sphere of world politics. PFIR is similar to Marxism, constructivism, and postmodernism in that they all posit that the masses underwrite hegemonic rule and, in so doing, ultimately have the means to do away with it. One difference is that PFIR emanates from the position of the subaltern; more specifically, the colonized’s colonized such as women, children, the illiterate, the poor, the landless, and the voiceless. Three major components are involved in PFIR in its analysis of world politics: culture, politics, and material structures. Also, eight common foci emerge in PFIR: intersectionality, representation, and power; materiality; relationality; multiplicity; intersubjectivity; contrapuntality; complicity; and resistance and accountability. PFIR gives rise to two interrelated projects: an empirical inquiry into the construction and exercise of power in daily life, and theory building that reflects this empirical base. A future challenge for PFIR is to elucidate how we can transform, not just alleviate, the hegemonies that persist around the world.

In seinem Beitrag operationalisiert Holger Pötzsch das Cybermedia-Modell von Espen Aarseth und Gordon Calleja und stellt eine Matrize für eine systematische Evaluierung von Videospielen vor deren Gebrauch im Unterricht vor. Ausgehend von den Feldern Zeichen und Repräsentation, Spielregeln und -mechaniken, Materialität und politische Ökonomie sowie institutionelle Rahmen, ermöglicht die Matrize das Stellen einer Reihe spezifischer Fragen, die vor didaktischer Nutzung reflektiert und geklärt werden müssen. Der Beitrag hofft so, einer kritischen Nutzung des Mediums Videospiel in schulischen Kontexten Vorschub leisten zu können.

ZusammenfassungDieses Kapitel führt in Verfahren zur Datenselektion- und transformation ein. Sie lernen, wie Sie mit regulären Ausdrücken Suchmuster formulieren, um unstrukturierte Daten aufzubereiten, wie Sie Elemente aus Webseiten mit CSS-Selektoren und XPath extrahieren und wie Sie Datenbanken mit SQL abfragen. Zudem erfahren Sie, wie Matrizen in verschiedene Formen gebracht werden und warum sich das lohnt.Im Online-Repositorium unter https://github.com/strohne/cm finden Sie begleitend zum Kapitel weitere Materialien, auf die wir im Text mit * verweisen.

Abstract Death and commemoration were crucial to Herbert’s poetic career: his first poetry published in print was his commemorative verse for his mother, Memoriae Matris Sacrum; Nicholas Ferrar made Herbert’s own pious death the entryway to the printed Temple in his prefatory epistle; and later editions of The Temple accreted commemorative paratexts, making the volume itself a commemorative work. The work of the church monument and that of devotional poetry are fundamentally similar, both representing what is absent—the divine and the deceased subject—through material form and figurative representation. Close reading of Memoriae Matris Sacrum and the Herbert monument at Montgomery reveal the shared complexities and ironies of the poetic and plastic forms. In ‘Church-monuments’ Herbert builds on and ‘dissolves’ the ‘monumental’ form of reading, a textual dissolution that reflects the paradoxes of contemporary literary cultures that exalted monumental texts while prioritizing excepting, recontextualization, and practical use.

Il presente capitolo e financo l’intero volume offrono l’opportunità di riflettere, a partire da casi concreti, sull’impatto generale che le trasformazioni digitali e le nuove esigenze di matrice pubblica hanno avuto sul settore dell’arte contemporanea. L’odierno Museo d’Arte Moderna e Contemporanea Mario Rimoldi rappresenta un esempio singolare e quantomai rilevante in un panorama museale come quello italiano che ha avuto un ritardo nella creazione di musei nel settore, per non parlare nella più generale esposizione pubblica di collezioni private. Non è un caso, dunque, che le Regole d’Ampezzo abbiano guardato precocemente anche a come sviluppare in ambito digitale le proprie attività legate al patrimonio artistico di cui sono custodi, intendendo andare oltre la mera vetrina online rappresentata invece da molti siti web museali. Il presente capitolo e fianco tutto il volume sono il frutto del progetto di analisi e adeguamento dell’identità digitale e dei sistemi informatici per gestire, studiare e valorizzare il ricco patrimonio di opere e materiali archivistici delle Regole d’Ampezzo in vista del cinquantenario dalla fondazione del Museo Rimoldi.