Le lin cultivé (Linum usitatissimum L.) est l’une des principales sources de lignanes, faisant de cette plante un modèle d’étude de cette voie du métabolisme spécialisé. Les principaux lignanes de lin dérivent de composés optiquement actifs, en particuliers les stéréoisomères du sécoisolaricirésinol qui sont synthétisés à partir de pinorésinol via laricirésinol. Les principales enzymes impliquées dans la synthèse de ces stéréoisomères sont deux isoformes de pinorésinol-laricirésinol réductases (PLR) déjà caractérisées et possédant des énantiospécificitées opposées. Néanmoins l'action de ces deux réductases bifonctionnelles ne permet pas d'expliquer les profils d'accumulation complexes notamment de laricirésinol et ses dérivés observés dans les graines, tiges et suspensions cellulaires de lin. Afin de mieux comprendre les mécanismes mis en oeuvre menant à ces profils d’accumulation de lignanes chez cette plante, la recherche de nouvelles PLRs a révélé l’existence de deux nouvelles isoformes. L’analyse de l'expression des gènes ainsi que l'activité enzymatique in vitro de ces deux nouvelles PLR putatives, LuPLR3 et LuPLR4 ont été élucidées. LuPLR4, in vitro, présente une activité réductase uniquement du pinorésinol. Ce type d’activité est ici décrit pour la première fois en dehors de la famille Brassicées et permet d’expliquer en partie les profils d’accumulation complexes observés chez le lin. De par leurs propriétés biocides, les lignanes sont suspectés jouer un rôle dans les mécanismes de défense des plantes. Dans le cadre de ce travail, suite à une élicitation fongique à l’aide d’extraits de Fusarium oxysporum spp. linii, un agent pathogène commun du lin, l’analyse de l’expression des différents gènes codant les isoformes de PLRs a révélées une induction globale et coordonnée. En particulier, dans le cas de l’isoforme LuPLR1, des délétions et mutations dans la région promotrice de son gène ont permis de mettre en évidence une région impliquée dans la régulation de la réponse à l’élicitation par F. oxysporum. Cette région contient plusieurs boîtes W, sites de liaison putatifs pour des facteurs de transcription de type WRKY. Les facteurs de transcription WRKY jouent un rôle dans les réponses aux stress biotique et abiotique. Un facteur de transcription candidat LuWRKY36 a été isolé à partir de suspensions cellulaires traitées avec des éliciteurs de F. oxysporum ou de l'acide abscissique. En particulier, les expériences de gel-retard et DPI-ELISA ont montré la capacité de liaison de LuWRKY36 à la boîte W3 présente du promoteur du gène LuPLR1. Cette régulation a ensuite été confirmée in vivo. Nous rapportons également l'impact différentiel de l'élicitation par des extraits de F. oxysporum sur l’expression des gènes LuWRKY36 et LuPLR1 ainsi que la production de sécoisolaricirésinol dans les variétés de lin sensible (Barbara) et résistante (Baïkal) à la fusariose. Enfin, la pleine exploitation des nombreux effets bénéfiques (en santé humaine ou cosmétique notamment) du sécoisolaricirésinol et des autres composés phénoliques accumulés dans les graines de lin nécessitent la mise au point de procédés d’extraction “verts”, efficaces voir sélectifs. Nous rapportons ici que l’utilisation de solvants eutectiques de type NADES (Natural Deep Eutectic Solvent) qui couplée à une extraction assistée par ultrasons, dans le cadre d’un procédé de type cracking, utilisant comme matériel de départ un coproduit d’extraction de l’huile de lin produit de manière innovante, permet d’obtenir des rendements d’extraction élevés et sélectifs de ces différents composés d’intérêt dans le cadre d’une démarche d’éco-extraction. / L. usitatissimum is one of the richest sources of lignans. Main flax lignan is optically active secoisolariciresinol that is synthesized from pinoresinol via lariciresinol. Key enzymes involved in the synthesis of this lignans are two isoforms of pinoresinol-lariciresinol reductases with opposite enantiospecificity. The action of bifunctional reductase does not allow for an explanation for the accumulation of lariciresinol and its derivates in seeds, stem and cell suspension. To try and better understand complex lignan profile we report expression and activity of two new putative PLRs, LuPLR3 and LuPLR4. LuPLR4 in vitro acts only as pinoresinol reductase what has only been seen in Brassicaceae family until now. Lignans play a role in plant defense. All PLRs are upregulated following Fusarium oxysporum attack, a common flax pathogen. Promoter deletions and mutation evidenced region involved in regulation of LuPLR1 gene response to Fusarium. The region contains several W boxes, putative binding sites for WRKY transcription factors. WRKY transcription factors play a role in response to biotic and abiotic stress. We have isolated LuWRKY36 from two cell suspension treated with Fusarium oxysporum or abscisic acid. Gel-shift assay and DPI-ELISA showed binding of LuWRKY36 to W box present in the LuPLR1 gene promoter. This regulation was also confirmed in vivo. We also report the differential impact of F. oxysporum elicitation on LuWRKY36 and LuPLR1 gene expression and secoisolariciresinol production in flax cultivars Barbara (Fusarium sensitive) and Baikal (Fusarium tolerant). Many beneficial effects of secoisolariciresinol and other phenolic compounds found in flax require “green” extraction and sometimes targeted purification of a specific compound. We report here that natural deep eutectic solvents using ultrasound assisted extraction can extract phenolic compounds from flax seed coat and that results indicate that by tuning different parameters of extraction we can target purification of desired plant product.

La tesi studia l’opera del war poet inglese Isaac Rosenberg (1890-1918) con l’obiettivo principale di analizzare l’influenza della sua formazione pittorica sulla produzione poetica, un aspetto che, seppur generalmente riconosciuto, è stato poco approfondito dalla critica. I primi tre capitoli esaminano il contesto sociale, culturale e artistico in cui Rosenberg visse prima di arruolarsi nell’esercito; in particolare, viene presentata la comunità ebraica dell’East End di Londra, il suo coinvolgimento nella Prima Guerra Mondiale, la scena artistica di inizio ventesimo secolo. Lo studio considera anche la scuola d’arte da lui frequentata, la Slade, la sua limitata produzione pittorica e le sue riflessioni di estetica, contenute nelle lettere e nella prosa. Il quarto capitolo, fulcro della tesi, propone un’analisi dei testi poetici che mira a evidenziare come il poeta abbia sfruttato l’esperienza di pittore nella scrittura, specialmente nella war poetry. Tra le strategie identificate, vi sono l’utilizzo simbolico dei colori, l’imagery relativa a luce e buio, l’adozione di una particolare prospettiva, la commistione tra astratto e concreto. Tali tecniche vengono lette come tentativi di rispondere alla difficoltà di rappresentazione e comunicazione dell’esperienza bellica. / The thesis studies the works of English war poet Isaac Rosenberg (1890-1918) with the main aim of analysing the influence of his pictorial training on his poetic production, an aspect which has been generally acknowledged, but scarcely investigated by critics. The first three chapters examine the social, cultural and artistic context in which Rosenberg lived before enlisting in the army; in particular, the focus is on the Jewish community of London’s East End, the involvement in the First World War, and the art scene of the early Twentieth century. The study also considers the art school he attended, the Slade, his limited pictorial production, and his thoughts on aesthetics, as included in the letters and prose. The fourth chapter, core of the thesis, proposes an analysis of the poems which aims to show how Rosenberg exploited his experience as a painter in his writing, especially in the war poetry. Among the identified strategies are the symbolic use of colours, the imagery related to light and shadow, the adoption of a particular perspective, the fusion of abstract and concrete. These techniques are seen as attempts to respond to the difficulty of representing and communicating war experience.

This bachelor’s thesis is based on the charred archaeobotanical material from a settlement at Eikebakken, Norway dated to the end of Bronze Age. The study focuses on determining the potential use of weeds and the oil plant flax (Linum usitatissimum). The archaeobotanical samples contained large amounts of charred flax seeds, and to determine whether it was used for oil or textile production a morphometric study of the material was undertaken and compared to other morphometric studies from Northern Europe. An experiment on modern flax seeds, carbonised at different temperatures, was used to expand current knowledge about how flax seeds change through the carbonisation process and why flax seeds are so rarely preserved in prehistoric contexts. The experiment results compared to the carbonized flax seeds from Eikebakken are shown with different diagrams and visualisations. The morphometric analysis together with the experiment provides new knowledge about the flax seeds complications with preservation and that flax in Norway's earliest stages was most likely grown for textile fibres, a contradiction to earlier assumptions.

Les éco-composites s'imposent progressivement comme une alternative à certains matériaux classiques. L'utilisation de fibres végétales en guise de renfort permet en effet d'améliorer les performances environnementales de ces matériaux ainsi que leurs propriétés spécifiques élevées. Dans ce contexte, cette étude propose d'élaborer un éco-composite sandwich dont les peaux sont constituées d'une résine thermoplastique innovante associée à des fibres de lin et à une âme en balsa. Tout d'abord, les comportements statiques de la résine et de l'âme sont analysés. Par la suite, le composite renforcé de fibres de lin constituant les peaux du sandwich est étudié. Les caractéristiques élastiques principales du pli UD en contraintes planes sont déterminées. De plus, une analyse des mécanismes d'endommagement est effectuée au moyen de la technique d'émission acoustique. Le comportement des poutres sandwiches sollicitées en flexion est ensuite étudié. Une attention particulière est portée à la compréhension des modes de rupture et à l'influence des variations locales des propriétés mécaniques de l'âme. Par ailleurs, certaines propriétés dynamiques de cette structure sont explorées, notamment son comportement en fatigue et sa réponse à l'impact afin de discuter de sa durabilité. Enfin, une étude expérimentale du comportement vibratoire des poutres composites et sandwiches est réalisée. Le rôle des différents constituants dans l'amortissement global des vibrations est discuté au moyen d'une modélisation par élément finis. L'ensemble des propriétés déterminées sont comparées à celles des matériaux non bio-sourcés, afin de situer ses performances. / Bio-based composites appear to be very promising alternatives to traditional composites. The use of natural fibres as reinforcement reduces the environmental impact of these materials and their specific properties are significantly increased. In this context, this work focuses on the manufacturing and the mechanical characterization of a bio-based sandwich structure. The skins are made of an innovative thermoplastic resin associated with flax fibres. The core is made of balsa wood. First, quasi-static analyses are performed on the different components. Then, the tensile properties of the composite skins are studied. Moreover, the main damage mechanisms are identified and described by means of the acoustic emission technique. Next, the flexural behavior of the whole sandwich structure is studied. Particular attention is paid to the detection and prediction of the main fracture modes. Moreover, the statistical spreads of the material properties of the balsa core are taken into account. In addition, cyclic fatigue and impact tests are performed to investigate the behavior of this structure under dynamic loads, and to discuss whether or not this material could be suitable for potential semi-structural applications. Finally, experimental analyses of the vibration behavior of composite and sandwich beams are performed. The contributions of the different components to the global damping properties of the sandwich structure are analyzed by means of a finite elements model. This work also compares the properties of this bio-based sandwich to those of traditional materials, in order to benchmark its mechanical performances with a view to further industrial usage.

Cílem této diplomové práce bylo navrhnout moduly určené k demonstraci a testování některých obvodů, používaných v automobilové technice. Jedná se o LIN transceiver NCV7420 a osmivýstupový výkonový budič AMIS-39101. Návrh spočíval ve vybrání a popisu parametrů vhodných podpůrných obvodů, vytvoření celkového schématu a navržení desky plošných spojů tohoto modulu s ohledem na kompaktní rozměry a předpokládané testy. Dalším krokem byla tvorba firmware řídicího mikrokontroléru (C8051F344), jež zajišťuje LIN komunikaci, řízení budiče a základní monitorovací funkce. Poslední část popisuje software pro hostitelský PC umožňující komfortní řízení sítě složené z těchto modulů. Pro úplnost byl tento projekt doplněn o přehled vlastností sběrnice LIN a metodiky testování LIN transceiveru z hlediska funkčních parametrů i některých EMC měření. V příloha obsahuje kompletní schéma modulu, výkresy desek plošných spojů, seznam řídicích příkazů a fotografie modulu.

Ce travail vise à étudier le comportement mécanique des composites renforcées par des fibres de lin ainsi que le comportement mécanique et hydrique des composites hybrides. Un taux de porosité élevée observée chez ces matériaux conduit à une dégradation des propriétés mécaniques. Des essais de traction et de flambement avec suivi par émission acoustique ont permis d’identifier les mécanismes d’endommagements qui règnent dans ces matériaux et à mettre en évidence leur chronologie d’apparition. Des observations microscopiques des faciès de rupture ont permis de valider ces résultats. Une optimisation des propriétés mécaniques et notamment en termes de réduire le taux de porosité a été testée et ceci en insérant des fibres de carbone dans la structure. Les résultats ont montré que la position des fibres de carbone est primordiale dans l’amélioration des propriété hydrique et mécaniques. / This work aims to study the mechanical behavior of composites reinforced by flax fibers as well as the mechanical and water behavior of hybrid composites. A high porosity rate observed in these materials leads to a degradation of the mechanical properties. Tensile and buckling tests with acoustic emission monitoring have identified the mechanisms of damage that reign in these materials and highlight their chronology appearance. Microscopic observations of fracture facies validated these results. An optimization of the mechanical properties particularly in terms of reducing the porosity rate has been tested by inserting carbon fibers in the structure. The results showed that the position of carbon fibers is essential in the improvement of water and mechanical properties.

L'objectif de cette thèse est de développer de nouveaux matériaux isolants bio-sourcés pour le bâtiment qui contribuent à réduire leurs impacts environnementaux. Les matériaux développés doivent avoir une faible énergie grise et une faible empreinte carbone. Ils doivent également contribuer à réduire les besoins énergétiques des bâtiments tout en assurant un confort hygrothermique élevé des utilisateurs. Tout d'abord, des matières premières d'origine agricole (chènevottes, anas de lin, paille de blé, paille de colza et rafles de maïs) sont caractérisées d'un point de vue chimique, physique, hygrothermique et mécanique, dans la perspective de développer des composites bio-sourcés destinés à l’isolation des bâtiments. Leur composition chimique se révèle intéressante pour le développement d'un liant vert. Une étude visant à évaluer cette aptitude est donc réalisée. A l'issue de cette dernière, deux liants correspondants à des extractions réalisées sur les rafles de maïs et sur les fines de lin sont retenus. D'autres liants provenant de l’industrie sont également sélectionnés pour la confection de composites. Puis des composites sont fabriqués pour étudier l'influence des granulats, du liant, de la granulométrie des granulats, de la réalisation d'un pré-traitement alcalins des granulats et de la pression de compaction appliquée lors de la mise en œuvre des composites sur leurs performances hygrothermiques ainsi que leurs propriétés mécaniques. Enfin, la résistance à l'immersion accidentelle et à l'humidité ainsi que la réaction au feu des formulations les plus prometteuses sont étudiées. / The aim of this thesis is to develop new bio-based building insulating materials which contribute to reduce their environmental impacts. The developed materials shall have low embodied energy and low carbon footprint. They shall contribute to reduce energy needs of buildings and to ensure high hygrothermal comfort of users. First, raw materials from agricultural resources (hemp shiv, flax shiv, wheat straw, rape straw and corn cobs) are characterized from a chemical, physical, hygrothermal and mechanical point of view, with a aim of developing bio-based composites for the thermal insulation of buildings. Their chemical composition is interesting for the development of green binder. A study to assess this ability is carried out. At the end of the study, two binders corresponding to extractions performed on corn cobs and flax fines are developped. Other binders from industry are also selected for composite production. Then, composites are produced to study the influence of aggregates, binder, granulometry of aggregates, alkaline pre-treatment of aggregates and compaction pressure applied during the processing of composites on their hygrothermal performances and mechanical properties. Finally, the resistance to accidental immersion and humidity and the reaction to fire of the most promising formulations are studied.

Nel teatro shakespeariano è molto spesso presente un uso del tempo affatto moderno e connesso con le nuove tecnologie, se si considera come moderna la presenza massiccia nel canone di una temporalità realistica e cadenzata dal movimento delle lancette dell’orologio, vero oggetto rivoluzionario del nuovo modello temporale. Tra i tanti strumenti che Shakespeare impiega per la manipolazione dell’elemento temporale a livello di drammaturgia, uno è sembrato particolarmente innovativo e rilevante: la scadenza. Si è pensato che la presenza di questo elemento in circa un quarto della produzione shakespeariana potesse rappresentare, anche solo dal punto di vista quantitativo, un dato interessante e meritevole di esame approfondito. Si è infatti ritenuto che l’imposizione di un limite di tempo preciso e scandito dall'orologio all’interno del dramma testimoni non soltanto la sussistenza di un nuovo approccio alla temporalità, ma anche la familiarità del pubblico con un nuovo modo di pensare il tempo. Si è considerato inoltre che il legame tra la scadenza e una nuova concezione del tempo potesse risultare con maggiore evidenza mettendola a confronto con un altro elemento, rappresentativo invece di un pensiero più tradizionale: la profezia. Nella profezia si è infatti voluto vedere una sorta di antecedente della scadenza stessa, a causa di alcuni aspetti formali che le accomunano; allo stesso tempo, tuttavia, ci si è concentrati sull’aspetto che le differenzia, operante proprio sul piano temporale e tale da renderle emblematiche di due tradizioni culturali e teatrali vicine ma fondamentalmente differenti. / Shakespearian theatre often presents a use of time which is undeniably modern and connected to new technologies, if we consider as modern the presence, in the Canon, of a realistic kind of temporality, marked by the rhythm of the clock, the revolutionary object that characterizes the new temporal model. Among the techniques that Shakespeare uses to manipulate the temporal element on a dramaturgical level, one seemed to be particularly innovative and relevant: deadline. The presence of this element in about one fourth of Shakespearean production could represent, if only from a quantitative perspective, an interesting fact, worthy of in-depth analysis. The imposition of a precise time limit, marked by the clock, was thought to be a testimony both of a new approach to temporality, and of the audience's familiarity with a new way to conceive time. The connection between deadline and a new conception of time was thought to better emerge by comparing it to another element, more representative of a traditional way of thinking: prophecy. Prophecy was considered as a sort of precedent for deadline, because of some formal aspects that they have in common; at the same time, however, the work focused on their differences, that occur on the temporal level, so much so that they almost become symbols of two cultural and theatrical traditions that are close, but fundamentally different.

Robustness is a ubiquitous property of biological systems, however, underlying mechanisms that help reinforce the optimal phenotypes despite environmental or physiological perturbations are poorly understood. C. elegans development consists of four larval stages (L1-L4) and well-characterized invariant cell lineages, within which the heterochronic pathway controls the order and timing of cell-fates. Environmental or physiological stress signals can slow or temporarily halt larval stage progression; remarkably, however, temporal cell-fate progression remains unaffected. We show that two widely conserved signaling pathways, insulin and TGF- β, that regulate C. elegans larval stage progression in response to starvation and crowding, respectively, also regulate a rewiring of the heterochronic pathway so that cell-fates remain temporally anchored to appropriate larval stages. This rewiring is mediated by the nuclear hormone receptor DAF-12, and it involves a shift from the reliance on let-7-family microRNAs to the reliance on LIN-46 for proper downregulation of the transcription factor, Hunchback-like-1 (HBL-1), which promotes L2 cell-fates and opposes L3 cell-fates. LIN-46 (which is a homolog of bacterial molybdopterin molybdenum transferase (moeA) and human gephyrin) post-translationally inhibits HBL-1 activity. LIN-46 expression is repressed by the RNA-binding protein LIN-28 at the early stages to permit HBL-1 activity and hence the proper execution of L2 cell-fates. Our results indicate that robustness mechanisms of temporal cell-fate progression in C. elegans involves 1) coordinated regulation of temporal cell-fates and larval stage progression and 2) collaboration between translational regulation exerted by microRNAs and post-translational regulation exerted by LIN-46 to coordinate HBL-1 downregulation with stage progression.

Il presente lavoro propone un percorso terminologico inteso a tracciare l’evoluzione generale della terminologia delle fibre tessili in francese dal Settecento in avanti, con un’attenzione particolare alle neoformazioni nel dominio delle fibre tessili chimiche. In linea con i principi fondamentali degli studi più avanzati nel campo della terminologia diacronica, il lavoro si propone di rendere conto dell’evoluzione terminologica nel dominio oggetto di studio, mettendo in evidenza il valore culturale dei termini e il legame con lo sviluppo tecnologico e il contesto socioeconomico. Lo studio è articolato in cinque capitoli aventi per oggetto, rispettivamente: la descrizione del quadro teorico di riferimento, l’analisi dei principali studi sui tessili e le fibre tessili pubblicati in francese in due periodi - dal XVIII al XIX secolo e dal XX secolo fino ad oggi - , la costruzione del corpus di dominio e l’analisi linguistico-terminologica, focalizzata sui processi di formazione dei nomi delle fibre. In chiusura è presente un glossario contenente le schede terminologiche che analizzano i termini delle fibre tessili chimiche in francese e forniscono gli equivalenti in italiano e in inglese. / The thesis proposes a terminological path aimed at tracing the general evolution of French terminology relating to textile fibres from the 18th century onwards, with a specific focus on the formation of new terms in the domain of chemical textile fibres. In line with the fundamental principles of the most advanced studies in the field of diachronic terminology, the work aims to account for the evolution of terminology in the domain under study, highlighting the cultural value of the terms and the link with technological development and the socio-economic context. The study is divided into five chapters. The first chapter provides a description of the theoretical framework, while the second and third present analyses of the main French-published studies on textiles and textile fibres during two periods – from the 18th to 19th centuries and from the 20th century to the present, respectively. Chapter four presents a construction of the domain corpus, while the fifth chapter engages in a linguistic-terminological analysis, focused on the process of the formation of fibre names. At the end of the study is a glossary containing terminology sheets analysing the French terms given to chemical textile fibres, alongside equivalents in Italian and English.