Purpose – The purpose of this study is to enhance the understanding of how to successfully collaborate on digital platforms in the manufacturing industry by developing a contingency framework. To fulfill this purpose, the following research questions were derived: RQ1: Which challenges arise when collaborating on digital platforms in the manufacturing industry? and RQ2: How can collaboration challenges on digital platforms in the manufacturing industry be managed? Method – The study was conducted as an explorative, inductive single case study of a digital platform. More specifically, the study examined the development process of a digital twin platform created by a large high-technological company and its collaborative actors. In total, 21 interviews were conducted at eight different companies. The respondents all had experience of digital twin platforms, where some were working with digital twins sporadically and others on a daily basis. The data were analyzed through a thematic analysis. Findings – The analysis reveals that actors on digital platforms can face five types of challenges that hinder a successful collaboration: disadvantages of dependency, uncertainty regarding data management, varying customer needs, insufficient work methods, and unsuitable payment models. The analysis also reveals four strategies that can be used to address the challenges: transparency strategy, incentive model strategy, servitization strategy, and control strategy. Moreover, these findings are summarized in a contingency framework that explains which types of challenges that can be addressed with which strategies based on the specific prerequisites of each collaboration. Theoretical and practical implications – The study extends the digital platform literature by providing empirical evidence for several collaboration challenges among the actors on a digital platform, which has previously bee not been studied. Additionally, the study provides evidence of how these challenges can be addressed. Our framework helps manufacturing companies to successfully adopt digital platforms by providing managers with the tools to handle the required collaboration. Limitations and further research – The study is limited by a single case study of a specific digital platform. Thus, to extend the findings, further research that examines other contexts are recommended. Moreover, the establishment of the studied platform is currently in an early phase which limits the study to hypothetical challenges and management methods. To validate the findings, further research that examines a fully developed and implemented platform is recommended.

A principal motivação para o desenvolvimento do presente projeto de doutorado foi comparar as microestruturas e texturas resultantes da liga de alumínio 3003 obtida por lingotamento contínuo e semicontínuo. O processo “roll caster" (lingotamento contínuo em cilindros) tem sido crescentemente utilizado na indústria de laminação de alumínio. Produtos que antes sofriam altos graus de deformação durante seu processamento são hoje obtidos nas dimensões próximas da espessura final. Com o intuito de entender este processo relativamente novo, as microestruturas e as texturas (macrotextura e microtextura), ao longo da espessura, das chapas produzidas por lingotamento contínuo e por lingotamento semicontínuo (placas fundidas com 250 mm de espessura, seguido de homogeneização e laminação a quente) foram analisadas. Foi possível constatar que os materiais provenientes dos dois processos diferem bastante e que ao longo da espessura também há grandes diferenças. Foi possível observar que durante o processamento “roll caster" há considerável deformação plástica, com a formação de células de discordâncias e subgrãos. Foi possível observar, também, que a microestrutura, a morfologia e o tamanho de grão, da amostra “caster" bruta de fundição são mais homogêneos que na amostra laminada a quente. As duas chapas, a laminada a quente e a obtida por lingotamento contínuo, exibem forte gradiente de textura ao longo da espessura. A textura predominante nos dois processos, ao longo da espessura, é a do tipo latão {011}. A evolução da textura do material proveniente do processo “roll caster" também foi caracterizada após laminação e posterior recristalização, revelando a presença de componentes típicas de laminação e de recristalização de alumínio. Após laminação a frio com redução de 91% e posterior tratamento térmico de 400°C por 1 h, a chapa proveniente do processo “caster" apresentou uma textura de recristalização caracterizada pela presença da componente cubo (recristalização) somada à parcela de textura de deformação. No caso do alumínio e suas ligas, sabe-se que esta textura proporciona os melhores resultados para minimizar o efeito de orelhamento durante a estampagem. Outro ponto relevante do trabalho foi o aperfeiçoamento da técnica de extração de precipitados para a liga 3003, uma vez que, a extração de precipitados em ligas de alumínio é especialmente problemática, pois a maioria das partículas presentes dissolve-se até mais facilmente que a matriz de alumínio. Algumas técnicas foram testadas: 1. dissolução química em solução de iodo em metanol; 2. dissolução eletrolítica em solução de ácido benzóico e hidroxiquinolina em clorofórmio e metanol; 3. dissolução eletrolítica em solução de ácido perclórico, butil glicol, álcool etílico e água; 4. dissolução química em solução de fenol. A técnica que apresentou melhores resultados foi a dissolução química com fenol, onde foi possível separar os precipitados da matriz alumínio. Com o auxílio desta técnica foi possível analisar as transformações de fase do composto intermetálico Al6Mn durante tratamentos térmicos. Obtiveram-se dados da completa transformação da fase Al6Mn em alfa-AlMnSi, também conhecida na literatura como, transformação "six to alfa". A precipitação e os precipitados desempenham um papel importante na cinética de recristalização e no tamanho de grão final. Para se entender este comportamento, comparou-se uma chapa que sofreu tratamento térmico antes da laminação com outra chapa que foi laminada no estado bruto de fundição. Os resultados revelaram que a recristalização foi retardada na amostra, inicialmente, bruta de fundição. A precipitação ocorreu simultaneamente com a recristalização, com isso, os dispersóides precipitaram preferencialmente na microestrutura deformada, em subcontornos ou nas discordâncias isoladas, levando a um considerável atraso no rearranjo das discordâncias e na nucleação da recristalização. / The main reason for the development of this PhD Thesis was to compare the microstructures and textures of the 3003 aluminum alloy produced from continuous and semi-continuous casting processes. The roll caster process (continuous casting) has been increasingly used in the aluminum industry. Products usually obtained by means of heavy rolling operations in the past are nowadays obtained with dimensions close to the final ones using the roll caster technology. To understand this new process, microstructures and textures (macrotexture and microtexture) along the thickness of the sheet produced by continuos casting and semi-continuous casting (plates with 250 mm thickness, followed by homogenization and hot rolling) have been investigated. It was possible to verify that materials coming from these two processes did differ each other a lot mainly across the thickness. During roll casting the plastic deformation was large enough to promote the formation of dislocation cells and subgrains. It was also possible to notice that the microstructure, morphology, and grain size from as-cast sample are more homogenous than the ones found in hot rolled samples. Both the sheets obtained by hot rolling and continuous casting have shown a strong texture gradient across the thickness. The predominant texture in both processes is the Brass component {011} . The texture evolution from sheets obtained by roll casting was also determined after rolling and subsequent recrystallization. It shows the presence of typical components of rolling and recrystallization of aluminum. After 91% cold rolling and subsequent recrystallization at 400°C for 1 h, the cube component (recrystallization texture) and the deformation texture were observed. It is well known that this texture minimizes earing effects during deep drawing of aluminum products. Another relevant point in this work was the development of the technique for the extraction of precipitates for the aluminum 3003 alloy. The extraction of precipitates extraction is particularly problematic in aluminum because most of the particles tend to dissolve more readily than the aluminum matrix. Some of the techniques performed are the following: 1. chemical dissolution with iodine in methanol solution; 2. electrolytic dissolution with benzoic acid and hydroxyquinoline in chloroform and methanol; 3. electrolytic dissolution with perchloric acid, butyl-glycol and ethanol; 4. chemical dissolution with phenol solution. Chemical dissolution with the phenol solution was the technique that provided the best results. It was possible to separate precipitates from the aluminum matrix. With this extraction technique it was possible to analyze phase transformations of the intermetallic compound Al6Mn during heat treating of this alloy. The phase transformation of the Al6Mn compound into alfa-AlMnSi, also known as 6-to-alfa transformation, could be followed in detail by means of this technique. Precipitation plays an important role in the recrystallization kinetics and final grain size. Therefore, to understand this behavior, the roll cast aluminum alloy was cold rolled from two distinct starting conditions: as-cast and heat-treated (homogeneized) conditions. It was shown that recrystallization was delayed in the sheet rolled from the as-cast condition. Precipitation has occurred simultaneously with recrystallization, in such a manner that dispersoids did precipitate in the deformed microstructure, preferentially, at subgrain boundaries or at free dislocations. As a result, the rearrangement of the dislocations and further recrystallization nucleation has been significantly retarded.

A digital twin is an enabling technology that facilitates monitoring, understanding, and providing continuous feedback to improve quality of life and well-being. Thus, a digital twin can consider a solution to enhance one's mood to improve the quality of life and emotional well-being. However, there remains a long road ahead until we reach digital twin systems that are capable of empowering development and the deployment of digital twins. This is because there are so many elements and components that can guide the design of a digital twin. This thesis provides a general discussion for the central element of an emotional digital twin, including emotion detection, emotional biofeedback, and emotion-aware recommender systems. In the first part of this thesis, we propose and study the emotion detection models and algorithms. For emotions, which are known to be highly user dependent, improvements to the emotion learning algorithm can significantly boost its predictive power. We aimed to improve the accuracy of the classifier using peripheral physiological signals. Here, we present a hybrid sensor fusion approach based on a stacking model that allows for data from multiple sensors and emotion models to be jointly embedded within a user-independent model. In the second part of this thesis, we propose a real-time mobile biofeedback system that uses wearable sensors to depict five basic emotions and provides the user with emotional feedback. These systems apply the concept of Live Biofeedback through the introduction of an emotion-aware digital twin. An essential element in these systems guides users through an emotion-regulation routine. The proposed systems are aimed at increasing self-awareness by using visual feedback and provide insight into the future design of digital twins. We focus on workplace environments, and the recommendations are based on human emotions and the regulation of emotion in the construct of emotional intelligence. The objective is to suggest coping techniques to a user during an emotional, stressful episode based on her or his preferences, history of what worked well and appropriateness for the context. The developed solution has been studied based on usability studies and extensively compared to related works. The obtained results show the potentials use as an emotional digital twin. In turn, the proposed solution has been providing significant insights that will guide future developments of digital twins using several scenarios and settings.

Este trabalho tem como objetivo analisar as políticas de gestão para cidades brasileiras de fronteira internacional, para verificar se essas políticas contribuem para a integração regional entre seus países, visando à gestão compartilhada. Observou-se que há duas situações nas experiências do Brasil: um movimento social não governamental e outra que, apesar de existirem políticas regionais, não há gestão compartilhada, o que difere da experiência internacional das cidades francesas cujo movimento é governamental e há gestão compartilhada. Foram identificados a forma de organização e o papel das fronteiras na sociedade desde a origem até os dias atuais para compreender os desdobramentos contemporâneos nas relações de vizinhança internacional. A distinção do Tratado de Tordesilhas, em 1494, como a primeira concepção da fronteira linear no mundo a estabelecer os novos territórios das duas Américas, a portuguesa e a espanhola, foi fundamental para o entendimento histórico da conformação e a ocupação das fronteiras terrestres brasileiras. No período moderno, a fronteira adquire uma importância singular - é o limite da soberania nacional. As teorias concebidas no final do século XIX constituem a base da formulação dos modelos geopolíticos que se adotam na Europa e nas Américas do Norte e do Sul. No mundo atual, os conflitos entre as diferentes ou próprias nações separando-as por muros significam as práticas da exclusão entre os povos que se refletem com mais intensidade no espaço fronteiriço. Espaços de convívio se contrapõem aos fechados, abrindo os caminhos para a convivência nas fronteiras permeáveis. O método de trabalho consistiu em reconhecer, na pesquisa bibliográfica, publicações impressas e eletrônicas e nas visitas técnicas no Brasil e no exterior aos órgãos públicos, os elementos definidores para a base teórico-conceitual dos estudos de fronteira. Estes auxiliaram as análises sobre o tema proposto, permitindo uma reflexão mais profunda sobre os espaços fronteiriços e a sociedade que neles habita, especialmente no estudo de caso das cidades-gêmeas de Ponta Porã (Brasil) e Pedro Juan Caballero (Paraguai) na fronteira entre os dois países. As reflexões conclusivas levam, a partir das análises, a necessidade de o Estado, como responsável pelo planejamento do território nacional, contemplar nas políticas nacionais de forma integral, as estruturas espaciais da faixa de fronteira, permitindo que os estados e municípios possam construir o seu desenvolvimento sustentável com um novo instrumento de política pública: a gestão de forma compartilhada. / This academic work aims to analyze the management policy for the Brazilian cities located on the international border, in order to verify if these policies contribute to the regional integration between their countries, trying to reach shared management. During the research, two situations were appointed in the Brazilian experiences: one that shows a non-governmental social movement; and the other points out a non-shared management policy besides existing regional governmental policies, this situation is different from the international experience of the French border cities, for example. The kind of organization and the role of the border condition in the society have been identified, since their origin until the present days, to understand the contemporary consequences in the relations between neighbor countries. Having the Treaty of Tordesilhas in 1494 as the first to draw a border line in the world and to establish the new territories of the two Americas, the Portuguese and the Spanish, was fundamental to the historical understanding of the conformation and the occupation of Brazilian border land. In the modern period, the border acquires a singular importance - it is the limit of the national sovereignty. The theories designed in the late Nineteenth Century are the basis of the formulation of the geopolitical models adopted in Europe and North and South Americas. In todays world, the conflicts between different nations or nations themselves, separating them by walls, mean the practices of exclusion among people from different cultures that are reflected more intensely in bordering areas. Spaces of coexistence rise against enclosed areas, opening a way of new relations in these permeable bordering regions. The method used in this work was to recognize, in the bibliographic research, printed and electronic articles, and technical visits in public agencies, in Brazil and abroad, the defining elements for a theoretical-conceptual basis for the studies of the border. These ideas contributed for the analysis about the proposed subject, allowing a deeper reflection on the neighboring spaces and on the society that lives in these areas, especially in the case studied of the twin cities of Ponta Porã (Brazil) and Pedro Juan Caballero (Paraguay) on the border between the two countries. The conclusive reflections lead, based on these analyses, the need of the State, as the responsible for the planning of the national territory, contemplate a national policies in full, take the spatial structures of the bordering area, allowing states and municipalities to build their sustainable development with a new instrument of public policy: the management in a shared way.

As fronteiras estão cada vez mais presentes nas agendas (políticas), discursos e noticiários. No ínterim, os fluxos de capitais, informações, produtos, pessoas e veículos entre o Rio Grande do Sul/Brasil e a Argentina ofereceram um rico quadro para investigação acadêmica. O trabalho tem por intuito compreender os desdobramentos da segurança, da defesa e do comércio exterior em Uruguaiana. Este questiona como se organizam os sistemas de controle, circulação e segurança na estrutura urbana de uma cidade estratégica em região de fronteira do Sul brasileiro, enfatizando o caso do território uruguaianense. O município situa-se em uma localização comercial privilegiada, em tríplice fronteira. Beneficia-se de distância equidistante de Assunção, Buenos Aires, Montevidéu e Porto Alegre. Constitui-se como um importante corredor de passagem de mercadorias até Santiago e São Paulo, expressivos centros urbanos sul-americanos. Em 2015, teve uma movimentação de mais de 126 mil caminhões, 2,3 milhões de toneladas e US$ 8,5 bilhões de dólares. 1,1 milhão de indivíduos cruzaram a Ponte Internacional Getúlio Vargas – Agustín Pedro Justo. O estudo contou com pesquisa bibliográfica, coleta de dados secundários e ida a campo (na qual foram reunidos dados primários e aplicadas entrevistas). A interlocução com órgãos federais como a Receita Federal do Brasil e o Departamento da Polícia Federal foi importante para o conhecimento da realidade fronteiriça e a obtenção de estatísticas. Diferenças culturais e territoriais, falta de continuidade das políticas governamentais, mudanças constantes nas legislações e oscilações econômicas são alguns dos fatores que geram esta complexidade fronteiriça. / The borders are increasingly more present in the political agenda, speeches and news. In the meantime, the flows of financial capitals, information, products, people and vehicles between the state of Rio Grande do Sul/Brazil and Argentina offer a rich picture for academic research. The work is meant to understand the unfolding of safety, of defense and foreign trade in the city of Uruguaiana. This work questions how the control, circulation and urban structure safety systems are organized in a strategic city in the South border of Brazil, emphasizing the case of Uruguaiana’s territory. The city is located in a prime commercial location, in a triple border. It benefits from an equidistant distance from the cities of Assunção, Buenos Aires, Montevidéu and Porto Alegre. It is constituted as an important crossing corridor of goods up to Santiago and São Paulo, significant South American urban centers. In 2015, it had a transit of more than 126 thousand trucks, 2,3 million tons and US$ 8,5 billion. 1,1 million people crossed Getúlio Vargas – Agustín Pedro Justo International Bridge. The study included bibliographic research, secondary data collect and site visit (in which primary data were gathered and interviews were conducted). The interlocution with federal agencies (such as Brazil’s Federal Income Taxes and the Federal Police Department) was important for obtaining knowledge about the border reality and for gathering statistical data. Cultural and territorial differences, lack of continuity from government policies, constant changes in legislations and economic fluctuations are some of the factors that bring forth this border complexity.

The Tat protein export system transports folded proteins across the bacterial cytoplasmic membrane and the plant thylakoid membrane. In Escherichia coli, the Tat system is composed of the TatA, TatB and TatC proteins. TatB and TatC assemble into a multimeric receptor complex that recognises and binds the substrate, before the TatA protomers cluster at the TatBC complex to facilitate substrate transport. A genetic screen was devised to explore the oligomeric state of TatC, reasoning that the isolation of dominant negative TatC variants that inactivate the Tat system in the presence of a functional copy of wild type TatC would provide strong evidence TatC is an obligate oligomer. Single dominant negative TatC substitutions were isolated that were located in the first and second periplasmic loops of TatC. These substitutions did not prevent TatC from interacting with TatB, TatA, itself or with a Tat substrate. Blue Native PAGE analysis showed that the TatC variants were unable to form the 440 kDa TatBC complex. Surprisingly, the substitutions did not prevent TatC:TatC self-interactions in the periplasmic regions, detected by disulphide cross-linking, but they did abolish a substrate-induced interaction at the fifth transmembrane helix of TatC. Fluorescence microscopy experiments revealed that the dominant negative TatC variants prevented the polymerisation of TatA-YFP in vivo. These results show that TatC possesses at least two interaction interfaces and imply that the periplasmic loops are critical for the transition between substrate binding and TatA polymerisation. Accessibility of single cysteine substitutions in TatC was probed by PEG-Mal labelling in intact cells. TatB was shown to be important for the proper insertion of TatC into the membrane. The absence of TatA led to accessibility changes in the vicinity of the fifth transmembrane domain of TatC, where both TatA and TatB are known to dock. This suggests that TatA and TatB may share an overlapping binding site.

Kindred, an MFA exhibition held at the Tipton Gallery located in downtown Johnson City from Feburary 22nd to March 4th. Kindred presents two bodies of work, which are a collection of drawings, etchings, monoprints, and lithographs, that center around a personal mythology and symbolism of self-identity and discovery. These works explore the physical and spiritual connection behind being a fraternal twin through the metaphorical use of animal imagery. The ideas discussed in this paper center around the process of creating a personal mythology and symbolism through my observations of animals and how I relate that experience to other mythologies that inspire me. This process of creating narratives and iconography coincide with the writings of Joseph Campbell and Carl Jung. This paper also includes the inspiration of other artists, such as Beth Cavener and Dennis McNett, who also use animal imagery to explain a kind of kinship.

No description available.

L’extrusion biocatalytique, ou bioextrusion, est une technique d’extrusion réactive utilisant des enzymes comme catalyseurs. Cette technique est considérée en temps qu’étape intermédiaire, subséquente au prétraitement physico-chimique et précédente à l’hydrolyse enzymatique enréacteur fermé. L’utilisation de l’extrusion permet un procédé continu, facilement modulable et adaptable à des conditions de hautes consistances, de nombreuses biomasses et facilement transférable à l’échelle industrielle. Néanmoins, les données bibliographiques font ressortir la complexité des entrants et leurs interactions lors de la bioextrusion de biomasses lignocellulosiques. Les conclusions des bioextrusions de biomasses amidonnées soulignent l’importance de l’étude de l’influence de la concentration en substrat et en enzymes. Les résultats obtenus à partir de la bioextrusion des biomasses lignocellulosiques valident l’existence d’une activité enzymatique en extrudeuse malgré la contrainte thermomécanique et le temps de séjour limité. Lors de cette étape, l’hydrolyse de la fraction cellulosique est favorisée pour des milieux concentrés en substrat et en enzymes. Des modifications significatives des fractions cellulosiques cristallines et amorphes en surface, des réductions des tailles de particules, une dégradation visuelle des structures de la biomasse et l’augmentation de la sensibilité à la décomposition thermique, sont aussi observées sur la fraction solide. L’hydrolyse enzymatique des bioextrudats est prolongée en réacteur fermé. La bioextrusion permet des améliorations significatives des taux et vitesses de conversion des sucres sur le long terme, jusqu’à 48 h. Les gains observés sont relativement constants pour la paille de blé et augmentent avec le temps pour les écorces de bouleau et les résidus de maïs. Post-extrusion, la concentration en substrat influence négativement la conversion des sucres. Cependant, les plus-values de conversion du glucose lié à la bioextrusion de paille de blé sont principalement observables pour des concentrations en substrat et en enzymes élevées. À partir de 4 h, des baisses significatives de la conversion du xylose sont observées après bioextrusion. Les déstructurations de la fraction solide, déjà observées au cours la bioextrusion, se poursuivent en réacteur fermé. Les meilleurs résultats hydrolytiques aux niveaux des hautes charges en enzymes et en substrat sont associables aux bonnes conditions de mélanges caractéristiques des éléments bilobes. L’ensemble enzymatique est probablement réparti de façon plus homogène (mélange distributif) pour cibler plus de sites disponibles. De plus, le mélangé dispersif limite la proximité entre enzymes de même type et les gênes associées. Le procédé d’extrusion permet une agitation efficace, un bon transfert de masse et probablement un meilleur contact entre enzymes et substrat. Les moins bons résultats de conversion du xylose sont probablement à relier à des phénomènes d’adsorption non-spécifique, ou encore de désactivation des hémicellulases, provoqués par l’intensité des contraintes thermomécaniques et les résidus ligneux. Les bons résultats de déstructuration après bioextrusionsont associables à une action synergétique des contraintes mécanique et biochimique. Les analyses d’autofluorescence montrent l’évolution de la fraction ligneuse dans le processus de déconstruction de la fraction solide. Une production progressive de particules très fines,visiblement associée à la fraction ligneuse, est observée. Des complexes lignine-carbohydratessont aussi détectés dans la fraction liquide. Etant peu, voire pas hydrolysable par voie enzymatique, ces fractions hétéropolymériques sont un frein à la déconstruction. Si la déstructuration des lignines est probablement majoritairement liée au prétraitement alcalin, le procédé de bioextrusion provoque une diminution de la teneur en hétéropolymères de plus hautes masses moléculaires. / Biocatalytic extrusion, also named bioextrusion, is a reactive extrusion technique using enzymes as catalysts. Bioextrusion is considered as a link between the previous physico-chemical pretreatment (like alkaline extrusion) and the subsequent enzymatic hydrolysis in batch conditions. The extrusion allows a continuous, flexible and versatile process for high consistency media, easily transferable to the industrial level. However, complexity of both lignocellulosic biomass and lignocellulolytic enzymes and their interactions during the extrusion process are underlined by the literature. Numerous response surface methodology experiments with starchy biomass indicate that bioextrusion efficiency is mainly influenced by substrate and enzymes loading. Enzymatic activity during the bioextrusion process of lignocellulosic biomass is confirmed by the experiments despite the mechanical constraints and the limited residence time. During bioextrusion, best holocellulosic fraction hydrolysis results were obtained with high substrate and enzymes loadings. Significant modifications of the solid fraction like particule size reduction, visual deconstruction of the biomass structure, increased sensibility to thermal decomposition and the evolution of the surface exposure of crystalline and amorphous cellulose were observed. Enzymatic hydrolysis of the bioextrdates is prolonged in batch conditions. Clear improvements of speeds and rates of sugars conversion up to 48 h indicate a long term influence of the bioextrusion. Gain observed are steady for the pretreated wheat straw whereas it increases with time for corn residues and birch barks. Post-extrusion, a negative influence of the substrate loading is measured. However, best enhancements for the glucose conversion of pretreated wheat straw are detected for high substrate and enzymes loadings. From 4 to 48 h, significant losses in xylose conversion are measured with previous bioextrusion. Indicators of the solid fraction deconstruction, observed during the bioextrusion step, indicate a stronger biomass degradation after 48 h. Improvements of glucose conversion rates can be associated with good mixing conditions of the extruder, especially due to the use of kneading elements. Enzymes are probably more homogeneously distributed (distributive mixing) and can access more catalytic sites available. Moreover, dispersive mixing limits the enzyme jamming due to the biocatalysts concentration. Extrusion process permits an better agitation efficiency, good mass transfer conditions and probably a higher contact between substrate and enzymes. Lower xylose conversion results may be attributed to non-specific adsorptions or inactivation phenomena due to mechanical constraints and lignin residues. Good deconstruction results on the solid fraction may be associable with a synergetic action between mechanical and biochemical constraints. Autofluorescent signal analysis of the lignin fraction show its evolution during the deconstruction of the solid residue. During the hydrolysis, a progressive production of very small particles, appearing to be associated with the lignin fraction is observed. Lignin-carbohydrate complexes are also detected in the liquid fraction. These heteropolymeric complexes, difficult or even impossible for the enzymes to hydrolyze, are an obstacle to the biomass valorization. If lignin deconstruction is mainly due to the alkaline pretreatment, bioextrusion process seems to reduce the proportion of these heteropylymers with high molecular weights.

Anxiety disorders (ADs) and stress-related disorders are some of the most common psychiatric disorders in the United States. Like other c0mplex psychiatric illness, genetics and neuroimaging research has focused on understanding their underlying neurobiology. Areas within the fear-network play important roles in threat perception, fear conditioning/learning, cognitive processing, and modulation of fear responses including contextual modulation and extinction and have been implicated in ADs as well as stress disorders such as posttraumatic stress disorder (PTSD). The primary gap in the current search for underlying biological mechanisms is in whether biomarkers associated with disorders share genetic influences with the disorders they index. Therefore, the aims of this dissertation are: 1) to examine the shared etiology of PTSD and threat-related brain regions while accounting for trauma using a large sample of male twins who served in the military during the Vietnam War; 2) to elucidate the shared and specific risk factors (genetic, familial environment and unique environment) and their roles amongst fear and anxiety domains in children; and 3) to examine whether brain regions previously implicated in fear processing and anxiety are significantly associated with a genetic factor score indexing fear and anxiety measures in a child sample. Using biometrical twin modeling this dissertation produced several novel findings regarding etiology of PTSD, threat-related domains and associated brain morphometry. Analyses investigating brain morphometric differences as potential endophenotypes for PTSD provided preliminary evidence that their phenotypic association is largely accounted for by environmental influences, specifically trauma exposure. However, sample size-induced model instability limits the ability to make definitive conclusions. Examining domains of fear and anxiety in children suggested a substantial genetic overlap between the two. Finally, the incorporation of a genetic factor score derived from the results of the biometrical modeling of fear and anxiety provided preliminary evidence for a genetic relationship between fear/anxiety and brain regions of interest. Although these results should be interpreted within the context of important limitations, they provide clear evidence that additional research into the genetic relationship between brain regions and disorders with larger sample sizes is justified.