Les modifications post-traductionnelles des protéines constituent un niveau crucial de régulation de l'expression des gènes. Parmi elles, la conjugaison peptidique impliquant l'ubiquitine intervient entre autre dans la régulation de la stabilité protéique. La fixation de ce peptide de 76 acides aminés, extrêmement conservé, sous forme de chaîne de polyubiquitine, nécessite l'intervention de trois enzymes (E1, E2 et E3) et constitue un signal de dégradation de la protéine ainsi modifiée. Cette voie de régulation intervient dans de très nombreux processus biologiques. Les complexes SCF sont impliqués dans la voie de protéolyse ciblée. Ils représentent l' une des classes les plus fréquentes d'ubiquitine ligase E3 et ils sont composés de quatre sous-unités (Rbx, Cullin, SKP1, et F-box). La structure et la fonction des complexes SCF, ont été étudiées chez la levure, l'Homme et la plante modèle A. thaliana. Cependant, peu de travaux ont été réalisés chez des plantes cultivées, en particulier les céréales, telles que le blé. Cinq gènes codant pour la sous-unité Skp1 (TSK1, TSK3, TSK6, TSK11 et TSK16), cinq gènes codant pour la sous-unité F-box (ZTL, ATFBL5, EBF, TIR1 et ABA-T), un gène codant pour la sous-unité Cullin1 et un gène codant pour la protéine RBX du complexe SCF du blé, ont été isolés et clonés. Les différents tests d'interaction entre les quatre sous-unités du complexe SCF ont été réalisés par la méthode du double-hybride dans la levure en utilisant la technologie Gateway. Ces études ont montré que les deux protéines, TSK1 et TSK3, fixent spécifiquement différentes sous-unités F-box. Parallèlement, nous avons montré que la protéine TSK11 représente une structure particulière. Des études d'insertion/délétion sur la protéine TSK11 ont permis d'identifier un nouveau domaine indispensable à l'interaction. Les analyses par PCR semi-quantitative des différents gènes codant pour la sous-unité Skp1, dans trois tissus différents (feuille tige et racine), ont mis en évidence une expression constitutive des gènes TSK3, TSK6 et TSK11. Tandis que les gènes TSK1 et TSK16 sont exprimés préférentiellement dans les racines. Les analyses par PCR semi-quantitative sur des plantules de blé à différents stades de développement, ont mis en évidence une surexpression du gène TSK11 au moment de la floraison. Ce qui suggère que TSK11 est probablement un équivalent fonctionnel d'ASK1 chez Arabidopsis thaliana.

Submitted by LETICIA VILMA DOS SANTOS VIEIRA null (leticiavieir@hotmail.com) on 2017-09-22T15:22:13Z No. of bitstreams: 1 DISSERTAÇÃO_Letícia Vilma dos Santos Vieira.pdf: 2517417 bytes, checksum: 934c0060d04d2bb79afa7cb1c1f7b10a (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-27T18:54:34Z (GMT) No. of bitstreams: 1 vieira_lvs_me_araca.pdf: 2517417 bytes, checksum: 934c0060d04d2bb79afa7cb1c1f7b10a (MD5) / Made available in DSpace on 2017-09-27T18:54:34Z (GMT). No. of bitstreams: 1 vieira_lvs_me_araca.pdf: 2517417 bytes, checksum: 934c0060d04d2bb79afa7cb1c1f7b10a (MD5) Previous issue date: 2017-08-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Na inflamação alérgica, a histamina desencadeia papel crucial na indução de sintomas, tais como vasodilatação, broncoconstrição e produção de muco. O objetivo deste estudo foi investigar os efeitos da histamina na inflamação e no remodelamento das vias aéreas, avaliando para tanto a produção de muco e colágeno em modelo murino de inflamação pulmonar. Camundongos Balb/c machos de 20-25g foram estimulados, por via intratraqueal, com histamina em diferentes concentrações (10, 50 e 100 µM) e avaliados após 6, 24 e 48 horas. A partir dos dados resultantes do ensaio dose-resposta, foi realizado tratamento farmacológico, onde animais foram separados em 5 grupos (6 camundongos por grupo): Grupo 1 (PBS), controle não estimulado; Grupo 2 (Histamina), controle estimulado; Grupo 3 (Histamina + Loratadina); Grupo 4 (Histamina + Dexametasona) e Grupo 5 (Histamina + Dexametasona e Loratadina). Analisamos a migração de leucócitos no lavado broncoalveolar (LBA) e no tecido pulmonar. As alterações estruturais no tecido pulmonar e na traqueia foram avaliadas por análise histopatológica, bem como a produção de muco e deposição de colágeno usando Alcian blue/Periodic Acid Shiff e Tricômio de Masson, respectivamente. O sobrenadante do LBA e o tecido pulmonar foram coletados para quantificar os níveis SCF e CCL3 por ELISA de captura. A expressão gênica de Muc5ac, Gob-5, Col1a2 e receptores de histamina foi avaliada por RT-PCR em tempo real. Nossos resultados demonstram que a histamina induz inflamação das vias aéreas, com presença de infiltrado leucocitário no LBA e no tecido pulmonar. Além disso, os animais estimulados com histamina demonstraram aumento significativo na expressão gênica de Muc5ac, Gob-5 e Col1a2 no tecido pulmonar, produção SCF e CCL3 no LBA e pulmão, bem como apresentaram alterações estruturais na traqueia e no tecido pulmonar, tais como infiltrado leucocitário, presença de células caliciformes, produção de muco e depósito de colágeno. O pré-tratamento com dexametasona (DEX) inibiu a migração leucocitária no LBA e tecido pulmonar, e também diminuiu a expressão gênica de Muc5ac no tecido pulmonar, diminuiu a produção de SCF e CCL3 no LBA e pulmão, bem como reduziu a produção de muco e a deposição de colágeno no pulmão. Já o pré-tratamento com loratadina (LOR), bloqueador de H1, inibiu parcialmente a migração celular no LBA, mas não no tecido pulmonar, enquanto que a associação farmacológica entre DEX e LOR diminuiu significativamente a migração leucocitária tanto no LBA como no tecido pulmonar. Com base nos dados acima, sugere-se que a histamina induz inflamação das vias aéreas, promovendo a migração de leucócitos possivelmente através da produção de SCF e CCL3, bem como provoca alterações estruturais na traqueia e no tecido pulmonar, tais como produção de muco, deposição de colágeno, e esses efeitos tem a participação dos receptores H1 e H4. / In allergic inflammation, histamine exerts a crucial role in the induction of symptoms, such as vasodilation, bronchoconstriction and mucus production. The aim of this study was to investigate the effects of histamine in inflammation and airway remodeling, evaluating the mucus production and collagen in a murine model of pulmonary inflammation. Male Balb/c mice of 20-25g were challenged by intratracheal instillation of histamine at different concentrations (10, 50 and 100 μM) and evaluated after 6, 24 and 48 hours. From the data resulting from the dose-response assay, pharmacological treatment was performed, and animals were separated into 5 groups (6 mice per group): Group 1 (PBS), non-challenged control; Group 2 (Histamine), challenged control; Group 3 (Histamine + Loratadine); Group 4 (Histamine + Dexamethasone) and Group 5 (Histamine + Dexamethasone and Loratadine). We analyzed the recruitment of leukocytes in bronchoalveolar lavage (BAL) and lung tissue. Structural changes in lung tissue and trachea were assessed by histopathological analysis, as well as mucus production and collagen deposition using Alcian blue/Periodic Acid Shiff and Masson's Trichrome, respectively. BAL supernatant and lung tissue were collected for SCF and CCL3 levels quantification by capture ELISA. The gene expression of Muc5ac, Gob-5, Col1a2, and histamine receptors was evaluated by RT-PCR real time. Our results demonstrated that histamine induces airway inflammation, with presence of leukocyte infiltrate in BAL and lung tissue. In addition, histamine-challenged animals demonstrated a significant increase in the gene expression of Muc5ac, Gob-5 and Col1a2 in lung tissue, SCF and CCL3 production in BAL and lung, as well as structural changes in the trachea and lung tissue, such as leukocyte infiltrate, presence of goblet cell, mucus production and collagen deposition around the airways. Dexamethasone pre-treatment (DEX) inhibited leukocyte recruitment in BAL and lung tissue, decreased gene expression of Muc5ac in lung tissue, decreases SCF and CCL3 production in BAL and lung, as well as mucus production and collagen deposition in the lung. Already pre-treatment with loratadine (LOR), an H1 blocker, partially inhibited cell migration in BAL, but not in lung tissue, whereas the pharmacological association between DEX and LOR significantly reduced leukocyte recruitment in both the BAL and the lung tissue. Putting the above data together, we suggest that histamine induces airway inflammation, promoting the recruitment of leukocytes possibly through the production of SCF and CCL3, as well as causes structural changes in the trachea and lung tissue, such as mucus production, collagen deposition, and these effects might be mediated by H1 and H4 receptors.

The purpose of this thesis ‘Sustainable conscious fashion consumption from the perspective of Generation Z - With a focus on motivations’ is to provide the reader with deeper knowledge about Generation Z’s perception of sustainable conscious fashion and what motivates them to choose sustainable consumption. Further, this research gives insight into the decision process among Generation Z regarding fashion apparel. The thesis is based on two research questions which are (1) What are the motivations to consume sustainable conscious fashion among Gen Z and (2) How do psychological factors influence Gen Z decisions to consume sustainable conscious fashion? To be able to complete this thesis and answer the research questions, relevant theories have been analyzed and incorporated to create an understanding when analyzing the empirical data. The thesis was conducted using a deductive approach and a qualitative research method to acquire primary data. The data collection has been accumulated by doing semi-structured interviews with the aim to gain in-depth knowledge about Gen Z motivations to consume sustainable conscious fashion. The literature review includes theories that are in relation to the topics of (1) Sustainability, (2) Generation Z, and (3) Psychological Factors such as self-image and cognitive dissonance. Based on the literature review a conceptual framework (Figure 2.1) was created in which the liaisons between the different theories have been presented. The interview guide was created in accordance to the operationalism in order to present the empirical data in chapter 4, ‘Empirical findings’.Thereafter, an analysis based on the empirical findings are discussed in relation to previously presented theories in the literature review. It is concluded that the primary motives for purchasing apparel among Generation Z are to strengthen their self-image, whether it is to fit in or stand out. The generation cares about sustainability, which is expressed by purchasing eco-friendly foods and by considering their choices of transport. The findings show there is a lack of information provided by retailers and authorities, which translates into the consumers not being able to make sustainable choices regarding fashion consumption.

No description available.

No description available.

Several boom segments form the crane boom. These segments are often truss structures formed out of circular hollow sections, which are welded together forming the truss joints. A adequate modelling of these truss joints is very important for operational strength and life. Due to the large boom sizes, efficient models are used in the finite element method, generally built of beam elements. These models have problems capturing the proper bending moments working in the truss joints. This is caused by a insufficient portrayal of the joint stiffness. In the literature several modelling techniques with beam elements are proposed, which capture the joint stiffness better. These different modelling methods are implemented in a parametric boom section and compared with a shell element FE model. From this comparison the most appropriate modelling method is selected, which improve the portrayal of internal loads and nominal stresses. With these improved nominal stress values, it is investigated to implement a different fatigue assessment. The structural stress can be calculated from the nominal stress in combination with stress concentration factor (SCF) equations. To implement the structural stress method as fatigue assessment, several modelling and extrapolation methods have been compared. Which lead to a method for evaluating the structural stress in a efficient matter. This method is compared with existing SCF K truss joint equations, from which a new set of SCF equations is derived. These equations are constructed from a larger dataset, hold a wider validity range and fit better with the FE models. When applying these SCF equations with the improved beam modelling method in a boom section, the structural stress is not adequately captured. This is caused by unsymmetrical stressed braces in the K truss joints. Both the modelling methods and SCF equations account for uniformly stressed braces forming the truss joints. More research needs to be conducted to this uneven behaviour. If the structural stress method needs to be implemented with efficient FE models, submodels out of shell elements combined with beam elements are recommended. For fatigue evaluation with the nominal stress method, beam models which account for the local joint flexibility give sufficient realistic results. / Flera kranarmsegment bildar kranarmen. Dessa segment är ofta fackverk utformade av cirkulära ihåliga profiler, som är sammansvetsade och bildar fackverkslederna. En ordentlig modellering av dessa fackförband är mycket viktig för dess driftsstyrka och livslängd. På grund av storleken används finita elementmetoden, vanligtvis uppbyggt av balkelement. Dessa modeller har problem med att beräkna de korrekta böjmomenten som uppstår i fackverkslederna. Detta orsakas av en otillräcklig beskrivning av ledstyvheten. I litteraturen föreslås flera modelleringstekniker med balkelement som tar hänsyn till ledens styvhet bättre. Dessa olika modelleringsmetoder implementeras i en parametrisk kranarmsektion och jämförs med en FE-modell med skalelement. Med denna jämförelse väljs den mest lämpliga modelleringsmetoden, vilket bör förbättra skildringen av interna belastningar och nominella spänningar. Med dessa förbättrade nominella spänningsvärden, undersöks det att genomföra en annan utmattningsbedömning. Den strukturella spänningen kan beräknas utifrån den nominella spänningen i kombination med spänningskoncentrationsfaktor- (SCF) ekvationerna. För att implementera strukturella spänningsmetoden som utmattningsbedömning, har flera modellerings- och extrapoleringsmetoder jämförts. Detta leder till en metod för att utvärdera den strukturella spänningen effektivt. Denna metod jämförs med befintliga SCF-ekvationer, från vilka en ny uppsättning SCF-ekvationer härleds. Dessa ekvationer är konstruerade från en större datauppsättning, har ett bredare giltighetsområde och passar bättre med FE-modellerna. När man applicerar dessa SCF-ekvationer med den förbättrade balkmodelleringsmetoden i en kranarmsektion, uppsamlas strukturella spänningar inte tillräckligt, detta orsakas av ojämna spänningar i diagonalelementen i fackverkslederna. Både modelleringsmetoderna och SCF-ekvationerna tar hänsyn till jämnt spända diagonalelement som uppstår i fackverkslederna. Mer forskning bör göras över detta ojämna beteende. Om den strukturella spänningsmetoden måste implementeras med effektiva FE-modeller, rekommenderas undermodeller av skalelement kombinerade med balkelement. För utmattningsutvärdering med den nominella spänningsmetoden, ger balkmodeller som tar hänsyn till den lokala ledflexibiliteten tillräckligt realistiska resultat.

No description available.

(ENGLISH) Hematopoiesis is dependent on the actions of hematopoietic stem cells (HSCs). This process is tightly controlled through a complex array of extrinsic and intrinsic factors. Even though the hematopoiesis seems to be well conserved across the disparate vertebrate animals, erythroid and thrombocytic differentiation have changed during the evolution of mammals. Specifically, adult mammalian red blood cells have the unique feature of being enucleated, and mammalian thrombocytes are not individual cells, but fragments of megakaryocytes, instead. It is likely that these enhancements provided a survival advantage to early mammalian species; however, they also bring up the question of evolutionary origin of these cells that studied using zebrafish (Danio rerio) model. First, it was necessary to generate a toolbox of a recombinant cytokines and optimized culture media that allowed us to manipulate zebrafish hematopoietic cells ex vivo in liquid and clonal cultures. Interestingly, teleost species underwent an extra duplication event during their evolution and as a result, two copies (paralogs) of some of the genes are present in zebrafish. This was also the case for majority of the cytokines from our toolbox and here, we provide functional characterization of these paralogs. Strikingly, our results...

Compression fracture specimens are ideally suited for miniaturization down to tens of microns. Fracture testing of thermal barrier coatings, ceramics and glasses are also best accomplished under compression or indentation. Compression fracture specimen of finite size with constant form factor was not available in the literature. The finite-sized specimen of edge cracked semicircular disk (ECSD) is designed which has the property of constant form factor. The novel ECSD specimen is explored further using weight function concept. This thesis, therefore, is mainly concerned with the design, development and geometric optimization of compression fracture specimen vis a vis their characterization of form factors, weight functions and isotropic points in the uncracked geometry. Inspired by the Brazilian disk geometry, a novel compression fracture specimen is designed in the form of a semicircular disk with an edge crack which opens up due to the bending moment caused by the compressive load applied along its straight edge. This new design evolved from a set of photoelastic experiments conducted on the Brazilian disk and its two extreme cases. Surprisingly, normalized mode-I stress intensity factor of the semicircular specimen loaded under a particular Hertzian way, is found constant for a wide range of relative crack lengths. This property of constant form factor leads to the development of weight function for ECSD for deeper analysis of the specimen. The weight function of a cracked geometry does not depend on loading configuration and it relates stress intensity factor to the stress distribution in the corresponding uncracked geometry through a weighted integral. The weight function for the disk specimen is synthesized in two different ways: using the conventional approach which requires crack opening displacement and the dual form factor method which is newly developed. Since stress distribution in the uncracked specimen is required in order to use weight function concept, analytical solution is attempted using linear elasticity theory. Since closed form solution for stresses in the uncracked semicircular disk is seldom possible with the available techniques, a new semi-analytical method called partial boundary collocation (PBC), is developed which may be used for solving any 2-D elasticity problem involving a semi-geometry. In the new method, part of the boundary conditions are identically satisfied and remaining conditions are satisfied at discrete boundary points. The classical stress concentration factor for a semi-in finite plate with a semicircular edge notch re-derived using PBC is found to be accurate to the eighth decimal. To enhance the form factor in order to test high-toughness materials, edge cracked semicircular ring (ECSR) specimen is designed in which bending moment at the crack-tip is increased significantly due to the ring geometry. ECSR is analyzed using nite element method and the corresponding uncracked problem is analyzed by PBC. Constant form factor is found possible for the ring specimen with tiny notch. In order to avoid varying semi-Hertzian angle during practice and thereby ensure consistent loading conditions, the designs are further modified by chopping at the loading zones and analyzed. Photoelastic isotropic points (IPs) which are a special case of zeroth order fringe (ZOF) are often found in uncracked and cracked specimens. An analytical technique based on Flamant solution is developed for solving any problem involving circular domain loaded at its boundary. Formation of IPs in a circular disk is studied. The coefficients of static friction between the surfaces of disk and loading fixtures, in photoelastic experiments of three-point and four-point loadings, are explored analytically to confirm with experimental results. The disk under multiple radial loads uniformly spaced on its periphery is found to give rise to one isolated IP at the center. Splitting of this IP into a number of IPs can be observed when the symmetry of normal loading is perturbed. Tangential loading is introduced along with normal loading to capture the effect of the composition on formation of IPs. Bernoulli's lemniscate is found to fit fringe order topology local to multiple IPs. Isotropic points along with other low fringe order zones including ZOF are ideal locations for material removal for weight reduction. Making a small hole in the prospective crack path at the IP location in the uncracked geometry might provide dual benefits: 1. Form factor enhancement; 2. Crack arrestor. Thus, this thesis describes experimental, theoretical and computational investigations for the design, development and calibration of novel compact compression fracture specimens.

L'activació sostinguda de Hog1 porta a una inhibició del creixement cel·lular. En aquest treball, hem observat que el fenotip de letalitat causat per l'activació sostinguda de Hog1 és parcialment inhibida per la mutació del complexe SCFCDC4. La inhibició de la mort causada per l'activació sostinguda de Hog1 depèn de la via d'extensió de la vida. Quan Hog1 s'activa de manera sostinguda, la mutació al complexe SCFCDC4 fa que augmenti l'expressió gènica depenent de Msn2 i Msn4 que condueix a una sobreexpressió del gen PNC1 i a una hiperactivació de la deacetilassa Sir2. La hiperactivació de Sir2 és capaç d'inhibir la mort causada per l'activació sostinguda de Hog1. També hem observat que la mort cel·lular causada per l'activació sostinguda de Hog1 és deguda a una inducció d'apoptosi. L'apoptosi induïda per Hog1 és inhibida per la mutació al complexe SCFCDC4. Per tant, la via d'extensió de la vida és capaç de prevenir l'apoptosi a través d'un mecanisme desconegut. / Sustained Hog1 activation leads to an inhibition of cell growth. In this work, we have observed that the lethal phenotype caused by sustained Hog1 activation is prevented by SCFCDC4 mutants. The prevention of Hog1-induced cell death by SCFCDC4 mutation depends on the lifespan extension pathway. Upon sustained Hog1 activation, SCFCDC4 mutation increases Msn2 and Msn4 dependent gene expression that leads to a PNC1 overexpression and a Sir2 deacetylase hyperactivation. Then, hyperactivation of Sir2 is able to prevent cell death caused by sustained Hog1 activation. We have also observed that cell death upon sustained Hog1 activation is due to an induction of apoptosis. The apoptosis induced by Hog1 is decreased by SCFCDC4 mutation. Therefore, lifespan extension pathway is able to prevent apoptosis by an unknown mechanism.