The transcription initiation is the first step in gene expression and an important regulation step in all living organisms. In bacteria, it has been proposed that DNA bending and its wrapping on the surface of E. coli RNAP might facilitate the opening of the transcription bubble, which is necessary for the initiation of gene transcription. In this work, it is shown the first structural study to evaluate a DNA wrapping model, including its length and the relative position in the bacterial transcription initiation complex (RP complex), assembled between RNA polymerase-σ70 holoenzyme (RNAP) and a λPR promoter (-100 to +30 wild type). RP complex was prepared and negatively stained with 2% uranyl acetate on a thin-carbon coated grid and the data acquisition of 500 images was performed in a JEM-2100 (JEOL, Japan) microscope equipped with an F-416 CMOS camera (TVIPS, Germany). Single particle analysis of 16,015 particles, grouped in 666 class-averages, was conducted using IMAGIC 4D software (Image Science, Germany) to obtain a three-dimensional model of the RP complex at 20Å resolution. After the rigid-body fitting of the RNAP crystallographic structure (PDB 4YG2) and the modeled DNA promoter, it was observed that the regions 1.2 and 4.2 of the σ70 subunit interacts with the consensus zones, -10 and -35 hexamers of the promoter. Furthermore, it was possible to observe that αCTDs (C-terminal domain) in both alpha subunits would be oriented to facilitate the interaction with the first and second UP-elements regions, respectively (centered around –50 and -75 positions in the promoter). These was enabled by the presence of the characteristics motifs helix-hairpin-helix in these domains. In addition, the downstream DNA, from the transcription bubble, appears to be inside the protein main channel, oriented in a way to enable interactions with the RNAP clamp and jaws. Finally, it was observed that the DNA wrapping has ~32 nm of total length and involves a promoter bent of ~255° around the RNAP surface. The 3D-model obtained in this study is the very first direct structural confirmation of the DNA promoter wrapping in a bacterial transcription initiation complex. / A iniciação da transcrição é o primeiro passo na expressão gênica e importante ponto de regulação em todos os organismos vivos. Em bactérias, foi proposto que o enovelamento do DNA na superfície da RNAP de E. coli pode facilitar a abertura da bolha de transcrição, necessária para o início da transcrição gênica. Neste trabalho, é apresentado o primeiro estudo estrutural direto para avaliar o comprimento do enovelamento do DNA e sua posição no complexo de iniciação da transcrição bacteriana (complexo RP), montado entre a holoenzima RNA polimerase-σ70 (RNAP) e um promotor λPR (-100 para +30, tipo selvagem). Amostras do complexo RP foram preparadas e contrastadas negativamente com 2% de acetato de uranila em uma grade com filme fino de carbono e a aquisição de 500 imagens foi realizada em um microscópio JEM-2100 (Jeol, Japão) equipado com uma câmera CMOS F-416 (TVIPS, Alemanha). A análise de partículas isoladas de 16.015 partículas, agrupadas em 666 médias de classe, foi conduzida usando o software IMAGIC 4D (Image Science, Alemanha) para obter um modelo tridimensional do complexo RP, a 20Å de resolução, estimado pelo critério de ½ bit. Após o ajuste de corpo rígido da estrutura cristalográfica da RNAP (PDB 4YG2) e do promotor de DNA modelado, observou-se que as regiões 1.2 e 4.2 da subunidade σ70 interagem com as zonas de consenso, hexâmeros -10 e -35, do promotor. Além disso, foi possível observar que os αCTDs (domínio C-terminal) em ambas as subunidades alfa estariam orientados para facilitar uma possível interação com a primeira e segundas regiões dos elementos UP, respectivamente (centradas em torno das posições –50 e -75 do promotor). Estas seriam possíveis devido à presença de alguns motivos de características hélice-grampo-hélice nesses domínios. Além disso, a região do promotor, downstream da bolha de transcrição, parece estar dentro do canal principal da proteína, orientado de forma a possibilitar interações com o clamp e jaw da RNAP. Finalmente, foi observado que o comprimento total do enovelamento de DNA envolve cerca de 32 nm e 255° de rotação do DNA ao redor da superfície da RNAP. Portanto, este modelo 3D é a primeira confirmação estrutural direta do enovelamento de DNA em um complexo bacteriano de iniciação da transcrição.

Linear springs with variable stiffnesses find some key roles in robotic applications. They are implemented into robotic devices for two main reasons, to increase energy efficiency of walking-running robots and prosthesis, and to get safe human-robot interaction at industrial robots. Being inspired from the human actuation system, a mathematical method to get mechanically adjustable linear springs is noted in the literature / antagonistically working two quadratic springs method. But the proposed solution requires two non-linear springs with quadratic spring characteristics and they are not readily available. Several solutions have been noted in the literature for the acquisition of such non-linear springs. At this thesis work, the solution is realized with a string wrapping around cam mechanism. Two different prototypes were designed and constructed and the second one was physically tested to validate the linear spring behavior. The results displayed good linear spring characteristics with different levels of adjustable spring stiffness. Beside the antagonistically working two quadratic springs method, three novel methods to get mechanically adjustable linear springs are introduced at this thesis. They are based on using hanging weights, an exponential characteristic spring and a linear translation spring respectively. The real prototypes were not manufactured but sample designs using string wrapping around cam mechanisms are made.

Ce travail de recherche est axé sur le développement de composites à liant phosphatique et fibres de renfort en verre E pour diverses applications structurales en Génie Civil. Dans une première partie, un bilan bibliographique nous permet d’identifier les principaux facteurs aux différentes échelles (nano, micro, méso et macro) ayant une influence sur le comportement global de composites à matrice minérale. Dans un second temps, les propriétés mécaniques et physico-chimiques des constituants sont présentées. Nous développons une méthodologie spécifique de caractérisation en traction, en compression et en cisaillement. Le développement de procédures expérimentales particulières en compression et en cisaillement permet l’identification des lois de comportement et l’évaluation des seuils d’endommagement et charges de rupture. La prévision des différents termes de rigidité élastique des systèmes composites est évaluée à partir d’expressions reprenant les principes de base de la micromécanique des composites. L’analyse du comportement à rupture est abordée au plan mésoscopique en considérant deux critères de résistance en plasticité, anisotropie (Tsai-Wu) et en contrainte normale, de cisaillement (Mohr-Coulomb). La deuxième partie de la recherche est consacrée à l’étude d’éléments structuraux mettant en oeuvre les formulations pultrudés de ces systèmes composites. L’expérimentation de poutres, présentant un rapport de la hauteur de la section à la portée de la poutre compris entre 1/15 et 1/50, met en évidence des modes de rupture spécifiques confirmant les faibles caractéristiques du matériau vis-à-vis de l’effort tranchant, du cisaillement interlaminaire et de la décohésion fibre/matrice. L’optimisation de la conception et du dimensionnement des poutres se poursuit en considérant des modifications d’ordre technologique : modification des sections par addition d’entretoises, confinement des sections par tressage circonférentiel, application d’un confinement par stratification directe. Pour chaque type de structures, nous cherchons à définir les limites de validité des méthodes de dimensionnement usuelles en examinant plus particulièrement la conformité des hypothèses de calcul (Navier-Bernoulli, Saint Venant), la cohérence des équations d’équilibre au regard de la cinématique dans chaque section. Dans un second temps, nous considérons des développements intégrant les non linéarités de comportement ou des modèles d’équilibre de type force adaptés à la redistribution interne des efforts tranchants. / This PhD thesis focuses on the development of E-glass reinforced Inorganic Phosphate Cement (IPC) matrix composites for structural applications in Civil Engineering. First, a bibliographical review highlights the main parameters occurring at different scales (nano, micro, meso and macro) influencing the global behaviour of the composite. Mechanical and physico-chemical properties of the different components are presented, followed by a characterization methodology in tension, in compression and in shear. The development of specific experimental procedures in compression and in shear leads to the identification of the constitutive equations and to the assessment of the damage and failure thresholds. The prediction of the different terms of elastic stiffness is assessed using micromechanical expressions. The failure is analysed at the macroscopic scale considering two failure criteria: Tsai-Wu and Mohr-Coulomb. The second part of the study is devoted to the analysis of loadbearing elements in glass reinforced mineral matrix. The realised beams show a height-to-span ratio between 1/15 and 1/50. The experimentation highlights specific failure modes confirming the weak shear performance of the composite in terms of shear force, interlaminar shear and fibre/matrix decohesion. Some technological modifications allow the optimisation of the design: the use of internal reinforcing struts, external confinement by fiber braiding and external wrapping. For each type of structure, we define the validity limits of the usual design methods examining the design hypotheses (Navier-Bernoulli, Saint Venant) and the equilibrium equations in function of the kinematics. In a second time, we consider the development of a force equilibrium model integrating a non-linear behaviour adapted to the internal redistribution of the shear forces.

Carbon nanotubes possess various unique and interesting properties. They have very high thermal and electrical conductivities, high stiffness, mechanical strength, and optical properties. Due to these properties, CNTs are widely used materials in a variety of fields. It is used for biotechnological and biomedical applications, as chemical and biosensor, in energy storage and field emission transistor. Experimentally synthesized CNTs are generally found in bundle form due to the strong vander Waals (vdW) at-traction between the individual tubes. To use CNTs in real life applications, we often require specific nanotubes with particular characteristics. The nanotube bundle is a mixture of various chirality, diameters and electronic properties (metallic and semiconducting). Only thermal energy is not sufficient to disperse nanotubes from the bundle geometry overcoming the strong vdW attraction between nanotubes. The hydrophobic and insoluble nature of CNTs in the aqueous medium makes the dispersion of CNTs even more difficult. So, it is a big challenge to get single pristine nanotube from the bundle geometry. Many experimental and theoretical studies have addressed the problem of nanotube dispersion from the bundle geometry. Ultrasonic dispersing method is a widely used technique for this purpose where ultrasonic sound is applied to agitate particles in a system. Other methods include using different organic and inorganic solutions, various surfactant molecules, different polymers as dispersing agents. In this study we extend our e orts to develop some better methods and improved dispersing agents. In this thesis, we address the problem of CNT dispersion. To address this issue, we rst give a quantitative estimation of the effective interaction between nanotubes. Next, we introduce different polymers (ssDNA and dendrimers) as external agents and show that they help to overcome the strong adhesive interaction between CNTs and make nanotube dispersion possible from the bundle geometry. For all of the works presented in this thesis, we have used fully atomistic MD simulation and DFT level calculations. We study ssDNA-CNT complex using all-atom MD simulation and calculate various structural quantities to show the stability of ssDNA-CNT complex in aqueous medium. The adsorption of ssDNA bases on CNT surface is driven by - interaction between nucleic bases and CNT. Using the potential of mean forces (PMF) calculation, we study the binding strength of the polynucleotide ssDNA for poly A, T, G, and C with CNT of chirality (6,5). From the PMF calculation, we show the binding sequence to be A > T > C > G. Except for poly G, our result is in good agreement with earlier reported single molecule force spectroscopy results where the sequence of binding interaction was reported to be A > G > T > C. To explore how the interaction between two CNTs mod-i ed in presence of ssDNA between them, we perform PMF calculation between the two ssDNA-wrapped CNTs. The PMF shows the sequence of interaction strength between two ssDNA-wrapped CNTs for different nucleic bases to be T > A > C > G. Thus, from PMF calculations we show the poly T to have the highest dispersion efficiency, which is consistent with earlier reported experimental study. Our PMF calculation shows that poly C and poly G reduce the attraction between two CNTs drastically, whereas poly A and poly T make the interaction fully repulsive in nature. We also present microscopic pictures of the various binding conformations for ssDNA adsorbed on CNT surface. We also study the dendrimer-CNT complex for both the PAMAM and PETIM dendrimers of different generations at various protonation states and present microscopic pictures of the complex. We calculate PMF between two dendrimer wrapped CNTs and show that protonated and higher generations (G3, G4, and so forth) non-protonated PAMAM dendrimers can be used as e ective agents to disperse CNTs from bundle geometry. We also study the chirality dependence of PMF respectively. Finally, we study the interaction of mannose dendrimer with CNTs and show that the wrapping of mannose dendrimer can drive a metal to semiconducting transition in a metallic CNT. We attribute the carbon-carbon bond length assymetry in CNT due to the wrapping of mannose dendrimer as the reason for this band gap opening which leads to metal-semiconductor transition in CNT. Thus, the wrapping of mannose dendrimer on CNT can change its electronic properties and can be used in the band gap engineering of CNT in future nanotechnology. Thus, the works carried out here in this dissertation will help to address the problem of nanotube dispersion from the bundle geometry which will in turn help to use CNT for various applications in diverse fields.

Fibre reinforced composites have higher specific strength and stiffness in comparison to metals. However, composites are susceptible to impact damage resulting in degradation of mechanical properties especially compression strength. Numerous studies have been conducted to improve the impact damage tolerance of composite laminates using modified resin systems, thermoplastic matrices, 3-D fibre architectures and through thickness reinforcement. This work is primarily focussed on incorporating non dissolvable polypropylene fibres (PP) in a thermoset matrix for improving the damage tolerance. Commingling and wrapping techniques have been investigated. PP fibres have been incorporated at the preform stage and hence do not adversely affect the viscosity of the resin during infusion. The healing effect of PP fibres on impact damaged composite laminates when heating is introduced has also been studied. High velocity impact test results showed that using commingled glass/PP fibres increased the total energy absorption of composite laminates by 20% due to the extensive plastic deformation of the PP fibres and through the use of toughening mechanisms in the form of resin cracking and delamination. It has been found that PP fibres provide protection to the glass fibres during low velocity impact loading, so fewer fibre breakages occur which lead to improved residual properties compared with pristine glass laminates. Compression after impact (CAI) tests showed that the residual strength as a percentage of non-impacted strength increased with percentage of PP fibres used. For impact of 20-50J, glass/epoxy laminates retained 32 45% of their compressive strength while laminates with 7%, 13% and 18% PP fibres retained 37 50%, 42-52% and 43-60% of their compressive strength, respectively. It was also observed that glass/PP woven laminates had better compressive strength retention (62 83%) than the glass/PP non-crimp laminates (37-50%). Composite laminates with high-modulus PP fibres (Innegra) exhibited higher residual compression strengths in comparison to laminates with lower modulus PP fibres. For 15-50J impact, glass/Innegra laminates showed residual compression strength of 50 63% in comparison to 39-60%; laminates without thermoplastic fibres exhibited 33 43% residual compression strength. Modulus of thermoplastic fibres appears to be important at higher energy levels. Healing of damaged commingled laminates produced a significant reduction in the damage area and a corresponding increase in CAI strength after heating at 200ºC; CAI strength of healed laminates is about 85% of undamaged samples in comparison to 60% for non-healed samples. A novel micro-wrapping technique, developed in this work, demonstrated significant reduction in damage area (46%) in comparison to the commingling method. Core wrapped laminates had higher residual strength (43-60%) than glass laminates (33-43%). Better PP distribution in core-wrapped composites helped to decrease the PP rich areas and the impact damage did not propagate easily in comparison to commingled composites. However due to the reduction in damage area, impact energy absorption in core wrapped laminates was lower than for commingled.

The dissertation deals with application of simulated swept paths of vehicles to road designs. Using software which generates simulated swept paths makes new demands on the designer, but Czech regulations do not stipulate the appropriate method of applying swept paths. The theoretical part of the dissertation analyses the theory of how a vehicle moves when passing through a horizontal road curve and a method of calculating a necessary extent of widening the road. The practical part compares swept paths generated by various software programs and differences between them. In order to verify the shapes and dimensions of the swept paths generated, the swept path of a real vehicle was measured. This swept path was then compared with the one generated, and the differences between them were evaluated. One of the software programs was chosen as a reference program, and its output was applied to a road design pursuant to valid regulations. The results obtained within the dissertation were used to develop certified methodology titled: „Methodology of widening road lanes in horizontal curves and of application of vehicles’ swept paths “.

This thesis deals with a design of new dot-wheels gearing. These wheels serve for closing of paper covers of tea bags. First of all the suggested spare options of the gearing shape are compared with the original. On the basis of the comparison results the gearing is solved as a substandard kind of involute gearing. The involute gearing is designed by the method of generalized parameters. For the gearing design the program GEARING – symetrical profile version 1.5. was used. Consequently this program was adapted for the case of the change of the instrument shape by the user. The kind of wheels material was designed. Further the way of wheels production for single-piece and batch production was also designed. At the end the economic evaluation of the wheels production with newly designed profile was done.

GIFTPARTIES, plan de negocio que consiste en la implementación de una tienda online bien estructura y diseñada en varias categorías de fácil acceso como: juegos educativos, manualidades y artes, regalos innovadores, entre otros. Nuestra idea de negocio está dirigida a padres de familias de 25 a 55 años que tengan hijos pequeños en un rango de 2 a 8 años. Nuestro segmento objetivo son padres de familia que trabajan y no disponen de tiempo suficiente para realizar la compra de regalos para los cumpleaños de los compañeros de sus hijos. Ofrecemos productos que permiten a los niños divertirse y desarrollar sus habilidades y capacidades psicomotrices. La tienda online está disponible los 365 días del año y las 24 horas del día y ofrece servicios como: envoltura del regalo, calendario online, servicio de delivery, servicio de recordatorio de eventos o cumpleaños y pasarela de pagos para compras con tarjetas de crédito o débito. Todo regalo contará con el servicio de elección de papel de regalo sea por género o diseño que más le agrade al cliente. El servicio de delivery va a estar enfocado en los distritos de Miraflores, San Isidro, San Borja, Surco, La Molina, Jesús María, Lince, Magdalena y San Miguel. Siempre nos preocuparemos en las necesidades de nuestros clientes a través de la creatividad e innovación. Se entregará lo acordado a tiempo, excediendo las expectativas. Realizaremos todo con exactitud y terminaremos con aquello a lo que nos comprometemos, cuidando siempre cada detalle. / GIFTPARTIES is a business plan that consists of the implementation of a very well structured and designed online store in several easily accessible categories such as: educational games, crafts and arts, innovative gifts, among others. Our business idea is aimed at parents of families from 25 to 55 years old who have small children in a range of 2 to 8 years. Our target segment is working parents who don't have enough time to buy gifts for their children's birthdays. GIFTPARTIES offers products that allow children to have fun and develop their psychomotor skills and abilities. The online store is available 365 days a year and 24 hours a day and offers services such as: gift wrapping, online calendar, delivery service, event or birthday reminder service, and payment gateway for purchases with a credit card or debit. It should be noted that all gifts will have the gift-wrapping service by gender or design that the customer likes the most. The delivery service will be focused on the districts of Miraflores, San Isidro, San Borja, Surco, La Molina, Jesús María, Lince, Magdalena and San Miguel. At GIFTPARTIES we will always care about the needs and desires of our customers through creativity and innovation. The agreed will be delivered on time, exceeding expectations. We will do everything with precision and we will finish with precision what we undertake, always taking care of every detail. / Trabajo de investigación

My project unfolds on three different scales:  Materials, Objects and a Space. A research on materials and new technique for their transformation, a creation of functional objects out of the transformed materials, and finally, a spatial environment for the created objects. Real-life site visits to various factories and craftsmen, discussions with makers, sourcing leftover materials, transforming materials into borderline art/design objects are among the key elements of my research methodology.  The three scales of my work are unified by the notion of Rituals. My understanding of rituals is not about creating a new religion but focuses rather on the activities in our everyday that can become rituals. It is about finding magic in the mundane. Daily routines and rituals are one of the main things that can keep us grounded, especially in a time of crisis. I believe that material explorations and working with the senses are important and relevant for the field of Spatial design and that my approach to engaging different scales within the project brings something new and yet not vastly explored.

Bakgrund: Trots plastfilmen negativa miljöpåverkan används den idag i hög utsträckning som förpackningsmaterial vid lastsäkring, detta då plastens materialegenskaper överträffar andra konkurrerade material. Plastfilm är ett förbrukningsmaterial, vilket gör att det inte kan återanvändas och stora mängder avfall skapas. Trots vetskapen om plastavfallets negativa påverkan på miljön läggs tonvikten på den ekonomiska aspekten när förpackningsmaterial diskuteras, medans miljön utlämnas eller har mindre fokus. Syfte: Studiens syfte är att utifrån identifierade faktorer utvärdera alternativa lastsäkringsmetoder som leder till en minskad användning av plastfilm utan att äventyra kvalitén på livsmedelsvaror under transport. Frågeställningar: (1) Vilka faktorer påverkar val av lastsäkringsmetod vid samlastade livsmedel? (2) Vilka alternativa lastsäkringsmetoder kan vidtas för att minska användningen av plastfilm i lastsäkringsprocessen? Genomförande: Denna studie motsvarar en enfallsstudie som är utförd hos Martin & Servera. Empiri insamling har främst skett via semi-strukturerade intervjuer och direkta observationer. I och med Covid-19 har även strukturerade intervjuer behövs genomföras. Utifrån observationer och intervjuer har en kartläggning av Martin & Serveras utgående logistik samt lastsäkringsprocess skett för att finna faktorer som påverkar valet av lastsäkringsmetod. Faktorerna har stått till grund vid framtagning av utvärderingskriterier, som har använts för att utvärdera alternativa lastsäkringsmetoder. De alternativa metoderna är funna genom intervjuer. Resultat: Totalt identifierades sju faktorer som påverkar val av lastsäkring metod: förpackningsformer, typ av lagersystem, lagerarbetare, krav/lagar/regleringar, typ av lastbärare, omslagsmaterialets egenskaper samt vilket typ av produkt som hanteras. Utifrån faktorerna framställdes utvärderingskriterier som sedan applicerades på fyra alternativa lastsäkringsmetoder (Plastskiva, Add-On Door Flex, 2 Kompletterande Dörrar samt Bioplastfilm). Samtliga metoder bidrog till minskad användning av plastfilm. Utifrån utvärderingskriterierna; Skydd & Stabilitet, Krav/Lagar/Reglering, Kostnad, Tidsåtgång, Miljö rekommenderas plastskivan som första alternativa lastsäkringsmetoden till plastfilm.