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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Etude des interactions dans la formation d'agrégats thermiques mixtes entre globulines de pois et béta-lactoglobuline : application à l'élaboration de gels acides / Study of moleculars interactions in the formation of thermal aggregats beteween pea globulins and beta-lactoglobulin : application to developement of acids gels

Chihi, Mohamed Lazhar 12 July 2016 (has links)
Dans un contexte de diversification des sources protéiques alimentaires, les protéines de pois représentent un ingrédient de choix et pourraient être associées à des protéines laitières comme celles du lactosérum dans la fabrication de nouveaux aliments. Dans ce travail, le comportement d’agrégation thermique (1h à 85°C), préalable à une gélification acide, des globulines de pois (Glob) seules et en mélange avec la β-lactoglobuline (βlg), a été étudié en fonction de la concentration totale en protéine, du ratio massique βlg/Glob et de la force ionique. La caractérisation des agrégats solubles a été réalisée par une combinaison de techniques analytiques telles que la détermination de l’hydrophobicité de surface, la quantification des ponts disulfures, la diffusion dynamique de la lumière (DLS), la chromatographie d’exclusion de taille (SEC-HPLC) et l’électrophorèse SDS-PAGE. La formation d’agrégats mixtes semble être gouvernée par des interactions intermoléculaires non covalentes, mais aussi des liaisons covalentes entre la βlg et les sous-unités de légumine notamment à faible force ionique (5 mM NaCl). Ces dernières semblent contrôler les caractéristiques méso-structurales des agrégats mixtes formés (haut poids moléculaire et diamètre réduit < 110 nm) comparativement aux agrégats formés de globulines seules (diamètre > 150 nm). Le deuxième volet de l’étude concernait la formation de gels acides obtenus par acidification au glucono-δ-lactone, soit à partir des agrégats mixtes solubles caractérisés précédemment, soit à partir de mélanges d’agrégats thermiques de chaque protéine obtenus séparément. Les différents paramètres liés à la cinétique d’acidification et à la gélification (temps et pH de transition sol/gel, propriétés mécaniques par rhéologie dynamique et analyse de la microstructure par Microscopie Confocale à Balayage Laser, capacité de rétention d’eau) ont été évalués. Les résultats démontrent que les agrégats mixtes issus des mélanges thermisés des deux protéines permettent d’obtenir des gels plus élastiques avec une structure fibrillaire plus ordonnée et moins poreuse, avec des caractéristiques proches de celles des gels formés d’agrégats purs de Blg. / In the context of protein source diversification, pea protein is a promising ingredient and may be associated with milk proteins such as whey proteins in the production of new food products. In the present work, the thermal aggregation (85°C - 1 h) of pea globulins (Glob) alone and in admixture with β-lactoglobulin (βlg), prior to acid gelation, was studied as a function of total protein concentration, βlg/Glob weight ratio and ionic strength. The characterization of soluble aggregates was carried out by combining different analytical methods such as surface hydrophobicity determination, disulfide bridge quantification, dynamic light scattering (DLS), size exclusion chromatography (SEC-HPLC) and SDS-PAGE electrophoresis. The formation of mixed aggregates seems to be governed by non-covalent intermolecular interactions, but also by covalent bonds between βlg and legumin subunits at low ionic strength (5 mM NaCl). The latter seem to control the structural features of mixed aggregates (high molecular weight and reduced diameter <100 nm) compared to pure globulin aggregates (diameter > 150 nm). The second part of this work investigated the formation of acid gels by glucono-δ-lactone, obtained either from soluble mixed aggregates such as characterized previously, either from mixtures of thermal aggregates of the two proteins prepared separately. The parameters associated to acidification kinetics and gelation (time and pH at sol/gel transition, mechanical properties by dynamic rheology and microstructure analysis by Confocal Scanning Laser Microscopy, water holding capacity) were evaluated. The results showed that mixed aggregates from heat-treated initial mixtures of the two proteins provides more elastic acid gels with a more regular and less porous fibrillar structure having close characteristics to those of pure βlg gels.
222

Novostavba hotelu v Brně / Hotel in Brno

Babycheva, Daryna January 2022 (has links)
Subject of this diploma this is prepare a documentation for the construction of a hotel. Designed object is located in the Brno city. The hotel meets the conditions of a three-star (***) economic standard. It is designed with 18 accommodation units, of which 2 rooms for disabled. The hotel accommodates only 38 people. There is a restaurant with a terrace in the hotel too. Underground garages primarily designed for parking cars of hotel visitors. The object is designed in a rectangular shape. The construction system of the hotel is combined. Perimeter masonry in the upper floors is made of ceramic blocks, inside are a reinforced concrete skeleton. The foundation structure is designed as a system of waterproof concrete. The floor structure is designed as reinforced concrete slabs. The roofing will be solved by a flat roof with a gravel layer. The whole building is insulated to meet all the requirements of energy consumption of buildings. The main entrance is oriented to the west. In front of the building there is a parking space for hotel guests.
223

Detection and quantification of post-translational modifications in non-invasive samples : Phosphoproteins as biomarkers and a market analysis of protein quantification technologies

Baudin, Sammi, Fjellström, Hillevi, Kraft, Aron, Lamberg, Erica, Rosenbaum, Måns, Sjöstrand, Hanna January 2023 (has links)
Post-translational modifications (PTMs) of proteins can be a sign and/or cause of disease. These modified proteins have the potential to be used as biomarkers for diagnostic purposes. However, research in the field is limited. The challenge of having an accessible way of diagnosing patients in time and at a low cost is crucial to improve public health. Blood samples or other non-invasive methods to detect diseases such as Alzheimer’s disease, Parkinson’s disease, Amyotrophic lateral sclerosis and cancers are of urgent need. This report investigates PTMs as possible biomarkers measurable in biofluids, such as blood, for diagnosis and prognosis. Biomarkers like phospho-tau and amyloid-beta are examined in the context of neurodegenerative diseases, as well as phosphorylations on neurofilaments, TAR DNA-binding protein 43 and α-synuclein. All of these are detectable in blood. Several PTMs with connection to different types of cancers are also investigated, such as F3-phosphopeptide and AFP-L3. It was found that many biomarkers for the detection of cancers can potentially be found in extracellular vesicles in blood. Methods such as ELISA, PEA, SomaScan, xMAP, SIMOA and mass spectrometry (MS) are all now available on the market to quantify these PTMs. MS has revolutionized the fields of protein detection in the past and has further evolved to being capable of protein quantification. ELISA has been prevalent for decades and laid the groundwork for improved methods such as xMAP and SIMOA that are easy to use and provide adequate sensitivity. SomaScan and PEA lead the way in dynamic range and multiplexing capacity with around 7000 and 3000 protein assays. The soon-to-be-released technology NULISA, with promising values in sensitivity and dynamic range, is also investigated here. Additionally, a written ethical analysis regarding the process and consequences of biomarker quantification through these technologies was performed. Although the investigated biomarkers are detectable in biofluids, using them as clinical diagnostic markers still poses a challenge, which is why further research in the field is needed. Through an increased knowledge of PTMs of proteins and the right use of platforms, clinical diagnostics and population screenings can be done more efficiently improving public health around the world.
224

BIOINFORMATIC MODELLING AND FUNCTIONALIZATION OF PEA PROTEIN THROUGH COLD DENATURATION WITH APPLICATIONS IN EXTRUSION, GELATION, AND EMULSIFICATION

Harrison Dale Brent Helmick (17467545) 29 November 2023 (has links)
<p dir="ltr">The impacts of processing on protein structure are of broad interest to the food science community including ingredient producers, product developers, and researchers. Processing and isolation steps induce protein structural changes which occur due to temperature based, shear, and chemical inputs, leading to denatured protein with different functionalities. However, exploration of the protein folding landscape as a way to intentionally modify protein conformation is not widely understood in food science. This particularly applies to cold denaturation, which is the structural changes in protein as the result of low temperature treatments.</p><p dir="ltr">This work has two primary goals. The first was to develop understanding of protein conformations resulting from cold denaturation and its implications for food textural properties. Pea protein was selected for this work since it is a source of plant-based protein that has recently grown in popularity and contains many hydrophobic amino acids that would make is susceptible to cold denaturation. Cold denaturation was studied using physicochemical techniques including differential scanning calorimetry, Fourier transform infrared spectroscopy, zeta potential, fluorescence spectroscopy, dynamic light scattering, and rheology. These techniques are used to characterize untreated pea protein, and proteins that have been modified using different combinations of ethanol, shear forces, acidic conditions, extrusion, and temperatures below 0°C. Significant physicochemical differences are found as the result of low temperatures, driven by an increase in surface hydrophobicity and electrostatic interactions. These differences led to protein gelation through hydrophobic forces, changing the nature of gels. Similarly, the increase in protein hydrophobicity leads to more stable emulsions from these products and unique fatty extrudates.</p><p dir="ltr">A second aim of this work developed bioinformatic models to interpret physiochemical data and provide mechanistic understanding of the process, as well as predict functional properties based on protein models. Strong correlations are found for the zeta potential, secondary structure, hydrogen bonds, and surface hydrophobicity. These models are used to convert data into physicochemical energy and used to provide reasonable estimates of mechanical properties of pea protein in extrusion, gelation, and emulsification. Together, this work shows that cold denaturation may be a useful tool for food product developers creating fatty and creamy textures. It also suggests bioinformatic modeling as a tool to estimate protein functionality, which could lead to tremendous time savings in process and product design.</p>
225

THE ROLE OF MORALITY, SELF-CONTROL, AND ENVIRONMENTAL EXPOSURE, ON OFFLINE- AND ONLINE AGGRESSIVE CRIMINOGENIC BEHAVIOUR: : A QUANTITATIVE STUDY ON SITUATIONAL ACTION THEORY AND ITS APPLICABILITY IN DIFFERENT ENVIRONMENTAL CONTEXTS

Riekwel, Annika January 2023 (has links)
According to Wikstörm’s (2012) Situational Action Theory (SAT), engaging incriminogenic behaviour is influenced by a person’s crime propensity, such as self-control and morality. Moral rules applied to a setting, and their degree ofenforcement, are stated as crucial since individuals are in constant interaction withtheir surroundings. Criminogenic exposure, such as having criminal friends and thetime spent with friends, is according to SAT (ibid.) influential on criminogenicbehaviour. The purpose of this study was, through hypothesis testing, to investigatethe applicability of SAT based on different environmental contexts. Aggressivecriminogenic behaviour was measured through bullying. Offline- andcyberbullying corresponded to aggressive criminogenic behaviour in differentenvironmental contexts. This study found that morality, self-control, andcriminogenic exposure, were significant in relation to offline bullying. Self-controland having criminal friends were significant in relation to cyberbullying. Genderwas used as a confounding variable and showed that girls are more prone tocyberbullying than boys, and that boys were more prone to offline bullying thangirls. Testing SAT applicability by comparing online and offline criminogenicbehaviour is understudied, further research on other online criminogenic behavioursis therefore encouraged, as well as the relationship between gender and anonymityas well as their influence in SAT.
226

IMPACT OF HOMOGENIZATION AND UHT PROCESSING ON THE EMULSIFICATION AND PHYSICAL PROPERTIES OF PEA PROTEIN BEVERAGES

Xiang Cheng (17583861) 10 December 2023 (has links)
<p dir="ltr">Pea protein is one of the most used plant proteins in food products, acting as an alternative to conventional animal protein sources due to its abundant, nutritious, and ease in supply chain characteristics. The objective of this study was to investigate the impact of homogenization and UHT processing parameters on the properties of protein emulsion. Protein emulsions (8% w/w pea protein isolate and 1% w/w sunflower oil) were freshly prepared prior to processing, and the untreated sample was considered as the control (NT). The pilot-scale aseptic processing system (APS) used in this study consisted of two coil-in-shell heaters and two coolers. Samples flowed through each section of the APS system following this order: balance tank, pre-heater, final heater, hold tube, pre-cooler, and final cooler. The homogenizer was located either after the pre-cooler (AC) or the pre-heater (AH) with a controlled temperature of 165F. A third setup was utilized by bypassing the homogenizer in the UHT system. An additional 8-hour continuous run was conducted to mimic a commercial manufacturing operation by recirculating the protein emulsion in the UHT system, and fouling detections were made using a non-intrusive sensor (NICS). 5% w/w soy protein, 1% w/w sunflower oil oil-in-water emulsion was also used for fouling tests. Protein concentration, pH and zeta potential, Cryo-SEM microscopic image, particle size distribution, flocculation index (FI), coalescence index (CI), viscosity and color data were collected and analyzed. The protein concentration had a 23.20 ± 4.00 %, 28.35 ± 5.02 %, 27.98 ± 5.05% and 21.38 ± 5.75% reduction for AC, AH, UHT and NT samples, respectively, when compared with the initial concentration in the formula. AC, AH, UHT and NT samples had pH values of 7.24 ± 0.01, 7.27 ± 0.01, 7.28 ± 0.02, 7.41 ± 0.01, and zeta potential values of -42.91 ± 0.89, -47.30 ± 0.91, -46.91 ± 1.40 and -50.11 ± 1.47 mV. AC sample had a smaller and NT sample had a bigger, respectively, mean weighted size D 4,3 value than AH and UHT samples, which could also be seen in Cryo-SEM images where only AC images contained more visually observable smaller particles. FI and CI for AC, AH and UHT indicated the formation of flocs but no irreversible aggregations were found. Shear-thinning AC, AH, UHT and NT samples had viscosity decreases from 4.00 to 3.56, 3.88 to 3.75, 4.02 to 3.79 and 10.42 to 9.56 mPa*s in 1 1/s to 100 1/s shear rate range. NT sample had a very noticeable color difference from the other three treated samples. Overall, AC samples had similar or better emulsion stability in all aspects than AH and UHT samples, suggesting that AC processing could potentially be used in the protein beverage industry for manufacturing products with improved shelf stability. Severe foulants buildups were neither observed nor detected by a non-intrusive continuous sensor (NICS) in the UHT system within 8 hours of process for both pea protein and soy protein emulsion, indicating that this UHT-homogenization processing can potentially be adapted to current industrial practices for higher-quality protein beverages.</p>
227

Agricultural Utilization of Brewers’ Spent Grains & Sawdust: Effects on Fertility of Soils and Productivity of Crops

Crosier, Joshua D. January 2014 (has links)
No description available.
228

Protein-based injectable hydrogels towards the regeneration of articular cartilage

Poveda Reyes, Sara 03 March 2016 (has links)
[EN] Articular cartilage is a tissue with low capacity for self-restoration due to its avascularity and low cell population. It is located on the surface of the subchondral bone covering the diarthrodial joints. Degeneration of articular cartilage can appear in athletes, in people with genetic degenerative processes (osteoarthritis or rheumatoid arthritis) or due to a trauma; what produces pain, difficulties in mobility and progressive degeneration that finally leads to joint failure. Self-restoration is only produced when the defect reaches the subchondral bone and bone marrow mesenchymal stem cells (MSCs) invade the defect. However, this new formed tissue is a fibrocartilaginous type cartilage and no a hyaline cartilage, which finally leads to degeneration. Transplantation of autologous chondrocytes has been proposed to regenerate articular cartilage but this therapy fails mainly to the absence of a material support (scaffold) for the adequate stimulation of cells. Matrix-induced autologous chondrocyte implantation uses a collagen hydrogel as scaffold for chondrocytes; however, it does not have the adequate mechanical properties, does not provide the biological cues for cells and regenerated tissue is not articular cartilage but fibrocartilage. Different approaches have been done until now in order to obtain a scaffold that mimics better articular cartilage properties and composition. Hydrogels are a good option as they retain high amounts of water, in a similar way to the natural tissue, and can closely mimic the composition of natural tissue by the combination of natural derived hydrogels. Their three-dimensionality plays a critical role in articular cartilage tissue engineering to maintain chondrocyte function, since monolayer culture of chondrocytes makes them dedifferentiate towards a fibroblast-like phenotype secreting fibrocartilage. Recently, injectable hydrogels have attracted attention for the tissue engineering of articular cartilage due to their ability to encapsulate cells, injectability in the injury with minimal invasive surgeries and adaptability to the shape of the defect. Following this new approach we aimed at synthesizing two new families of injectable hydrogels based on the natural protein gelatin for the tissue engineering of articular cartilage. The first series of materials consisted on the combination of injectable gelatin with loose reinforcing polymeric microfibers to obtain injectable composites with improved mechanical properties. Our results demonstrate that there is an influence of the shape and distribution of the fibers in the mechanical properties of the composite. More importantly bad fiber-matrix interaction is not able to reinforce the hydrogel. Due to this, our composites were optimized by improving matrix-fiber interaction through a hydrophilic grafting onto the microfibers, with very successful results. The second series of materials were inspired in the extracellular matrix of articular cartilage and consisted of injectable mixtures of gelatin and hyaluronic acid. Gelatin molecules in the mixtures provided integrin adhesion sites to cells, and hyaluronic acid increased the mechanical properties of gelatin. This combination demonstrated ability for the differentiation of MSCs towards the chondrocytic lineage and makes these materials very good candidates for the regeneration of articular cartilage. The last part of this thesis is dedicated to the synthesis of a non-biodegradable material with mechanical properties, swelling and permeability similar to cartilage. This material intends to be used as a platform in a bioreactor in which the typical loads of the joint are simulated, so that the hydrogels or scaffolds would fit in the recesses in the platform. The function of the platform is to simulate the effect of the surrounding tissue on the scaffold after implantation and could reduce animal experimentation by simulating in vivo conditions. / [ES] El cartílago articular es un tejido con baja capacidad de auto-reparación debida a su avascularidad y baja población celular. Se encuentra en la superficie del hueso subcondral cubriendo las articulaciones. La degeneración del cartílago articular puede aparecer en atletas, en personas con procesos genéticos degenerativos o debido a un trauma; lo que produce dolor, dificultades en la movilidad y degeneración progresiva que lleva al fallo de la articulación. La auto-reparación sólo se produce cuando el defecto alcanza el hueso subcondral y las células madre (MSCs) de la médula ósea invaden el defecto. Sin embargo, este nuevo tejido es un cartílago de tipo fibrocartilaginoso y no un cartílago hialino, el cual finalmente lleva a la degeneración. El trasplante de condrocitos autólogos ha sido propuesto para regenerar el cartílago articular pero esta terapia falla principalmente por la ausencia de un material soporte (scaffold) que estimule adecuadamente a las células. El implante de condrocitos autólogos mediante un hidrogel de colágeno no tiene las propiedades mecánicas apropiadas, no proporciona las señales biológicas a las células y el tejido regenerado no es cartílago articular sino fibrocartílago. Se han realizado diferentes enfoques para obtener un scaffold que mimetice mejor las propiedades y la composición del cartílago articular. Los hidrogeles son una buena opción ya que retienen elevadas cantidades de agua, de forma similar al tejido natural, y pueden imitar de cerca la composición del tejido natural mediante la combinación de derivados de hidrogeles naturales. Su tridimensionalidad juega un papel crítico para mantener la función de los condrocitos, ya que el cultivo en monocapa de los condrocitos hace que desdiferencien hacia un fenotipo similar al fibroblasto secretando fibrocartílago. Los hidrogeles inyectables han acaparado la atención en la ingeniería tisular de cartílago articular debido a su capacidad para encapsular células, su inyectabilidad en el daño con cirugías mínimamente invasivas y su adaptabilidad a la forma del defecto. Siguiendo este nuevo enfoque hemos sintetizado dos nuevas familias de hidrogeles inyectables basados en la proteína natural gelatina para la ingeniería tisular del cartílago articular. La primera serie de materiales combina una gelatina inyectable con microfibras poliméricas sueltas de refuerzo para obtener composites inyectables con propiedades mecánicas mejoradas. Nuestros resultados demuestran que hay una influencia de la forma y la distribución de las fibras en las propiedades mecánicas del composite. Además, la mala interacción entre las fibras y la matriz no es capaz de reforzar el hidrogel. Debido a esto, nuestros composites han sido optimizados mediante la mejora de la interacción fibra-matriz a través de un injerto hidrófilo sobre las microfibras, con resultados muy exitosos. La segunda serie de materiales se ha inspirado en la matriz extracelular del cartílago articular y ha consistido en mezclas inyectables de gelatina y ácido hialurónico. Las moléculas de gelatina proporcionan los dominios de adhesión mediante integrinas a las células, y el ácido hialurónico aumenta las propiedades mecánicas de la gelatina. Esta combinación ha demostrado la habilidad para la diferenciación de MSCs hacia el linaje condrocítico y convierte a estos materiales en buenos candidatos para la regeneración del cartílago articular. La última parte de esta tesis se dedica a la síntesis de un material no biodegradable con propiedades mecánicas, hinchado y permeabilidad similar al cartílago. Este material pretende ser empleado como plataforma en un biorreactor en el que se simulan las cargas típicas de las articulaciones, de forma que los scaffolds encajarían en los huecos de la plataforma. Su función es simular el efecto del tejido circundante en el scaffold después de su implantación y podría reducir la experimentación anim / [CA] El cartílag articular es un teixit amb baixa capacitat d'auto-reparació deguda a la seua avascularitat i baixa població cel·lular. Es troba en la superfície de l'ós subcondral cobrint les articulacions. La degeneració del cartílag articular pot aparèixer en atletes, en persones amb processos genètics degeneratius o degut a un trauma; produeix dolor, dificultats a la mobilitat i degeneració progressiva que finalment porta a la fallida de l'articulació. L'auto-reparació es produeix quan el defecte arriba fins a l'ós subcondral i les cèl·lules mare (MSCs) de la medul·la òssia envaeixen el defecte. No obstant això, aquest nou teixit format es un cartílag de tipus fibrocartilaginós i no un cartílag hialí, el qual finalment porta a la degeneració. El transplantament de condròcits autòlegs ha sigut proposat per a regenerar el cartílag articular però aquesta teràpia falla principalment per la absència d'un material de suport (scaffold) que estimuli adequadament a les cèl·lules. L'implant de condròcits autòlegs en un hidrogel de col·lagen per als condròcits no té les propietats mecàniques apropiades, no proporciona les senyals biològiques a les cèl·lules i el teixit regenerat no és cartílag articular sinó fibrocartílag. Diferents enfocs han sigut realitzats fins ara per a obtenir un scaffold que mimetitzi millor les propietats i la composició del cartílag articular. Els hidrogels son una bona opció ja que retenen elevades quantitats d'aigua, de forma similar al teixit natural, i poden imitar acuradament la composició del teixit natural mitjançant la combinació d'hidrogels naturals. La seua tridimensionalitat juga un paper crític per a mantenir la funció dels condròcits, ja que el cultiu en monocapa dels condròcits fa que aquests desdiferencien cap a un fenotip similar al fibroblàstic secretant fibrocartílag. Recentment, els hidrogels injectables han acaparat l'atenció en l' enginyeria tissular de cartílag articular degut a la seua capacitat per a encapsular cèl·lules, la seua injectabilitat en el dany amb cirurgies mínimament invasives i la seua adaptabilitat a la forma del defecte. Seguint aquesta nova aproximació hem sintetitzat dues noves famílies d'hidrogels injectables basats en la proteïna natural gelatina per a l'enginyeria tissular del cartílag articular. La primera sèrie de materials combina una gelatina injectable amb microfibres polimèriques soltes de reforç per a obtenir compòsits injectables amb propietats mecàniques millorades. Els nostres resultats demostren que hi ha una influència de la forma i la distribució de les fibres en les propietats mecàniques del compòsit. Més importantment, la mala interacció entre les fibres i la matriu no és capaç de reforçar l'hidrogel. Degut a això, els nostres compòsits han segut optimitzats mitjançant la millora de la interacció fibra-matriu a traves d'un empelt hidròfil sobre les fibres, amb resultats molt exitosos. La segona sèrie de materials està inspirada en la matriu extracel·lular del cartílag articular i ha consistit en mescles injectables de gelatina i àcid hialurònic. Les molècules de gelatina proporcionen els dominis d'adhesió mitjançant integrines a les cèl·lules, i l'àcid hialurònic augmenta les propietats mecàniques de la gelatina. Esta combinació ha demostrat l'habilitat per a la diferenciació de MSCs cap al llinatge condrocític i converteix a aquests materials en bons candidats per a la regeneració del cartílag articular. L'última part d'aquesta tesi és dedicada a la síntesi d'un material no biodegradable amb propietats mecàniques, inflat i permeabilitat similar al cartílag. Aquest material pretén ser utilitzat com a plataforma a un bioreactor que simula les cargues típiques de les articulacions, de manera que els hidrogels o scaffolds encaixarien als buits de la plataforma. La seua funció es simular l'efecte del teixit circumdant al scaffold després d / Poveda Reyes, S. (2016). Protein-based injectable hydrogels towards the regeneration of articular cartilage [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61392 / Premios Extraordinarios de tesis doctorales
229

Serial and Parallel Elastic Cable Driven Actuator (SPECA) to Achieve Efficient and Safe Human Robot Physical Interaction

Al-Ani, Al-Muthanna 01 January 2024 (has links) (PDF)
In this thesis, design, integration and validation of Serial and Parallel Elastic Cable Actuator (SPECA) is presented with an aim to enhance human-device interaction in cable-driven systems of wearable robots and to optimize actuator force and power delivery to the user. Adding springs in series and in parallel to the cables acted on the mechanical joint for motion or force control have been shown individually to reduce mechanical power consumption and therefore electrical power consumption. SPECA combines both serial elastic (SE) and parallel elastic (PE) components to explore the compounded effects on a dual cable driven system controlled by a single actuator. A bi-articulating winch attached to the actuator allows control of two cables to achieve a bidirectional control of a revolute joint. Expanding the control of the single actuator, the dual cables route to a mechanical clutch that can engage up to two external winches, or four cables, simultaneously. SPECA is built as an isolated system with only the two winches of the clutch leading to end effectors creating a design capable of being integrated into many cable driven systems. A Simulink model is developed of a simple two degree of freedom (DOF) system to confirm that SE and PE elements not only increase the effective range of a system but lower the mechanical power. SPECA undergoes static and dynamic experiments to explore SE and PE in an applied system confirming the conclusions of the model along with recommendations based on observed characteristics from the experiments. SPECA serves as an exploratory and modular proof of concept for the integration of SE and PE components into many cable driven systems.
230

A correlação entre jornada de trabalho e produtividade: uma perspectiva macroeconômica entre países

Gaspar, Willians Cesar Rocha 19 December 2017 (has links)
Submitted by Willians Gaspar (willians.gaspar@fgv.br) on 2018-01-22T16:33:59Z No. of bitstreams: 1 A Correlação entre Jornada de Trabalho e Produtividade - Uma Perspectiva Macroeconômica entre Países.pdf: 1651221 bytes, checksum: 10a95ba6074b04f5e4e0f6d88a9bf7b6 (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2018-01-24T12:00:40Z (GMT) No. of bitstreams: 1 A Correlação entre Jornada de Trabalho e Produtividade - Uma Perspectiva Macroeconômica entre Países.pdf: 1651221 bytes, checksum: 10a95ba6074b04f5e4e0f6d88a9bf7b6 (MD5) / Made available in DSpace on 2018-01-29T18:55:15Z (GMT). No. of bitstreams: 1 A Correlação entre Jornada de Trabalho e Produtividade - Uma Perspectiva Macroeconômica entre Países.pdf: 1651221 bytes, checksum: 10a95ba6074b04f5e4e0f6d88a9bf7b6 (MD5) Previous issue date: 2017-12-19 / This research has as general objective to identify the variables or contributing factors to subsidize the discussion about reduction of the Working Day. As a specific objective, what is proposed is to verify how these same variables affect Productivity. For both objectives the macroeconomic aspects of the countries analyzed are considered. The criterion for selecting these countries is based on the "ranking" of the OECD and World Bank database for the year 2013, considering all the major world economies, which together represent 65.22% of global GDP. The data extracted refer to the "Gross Domestic Product - GDP at (PPP) - Purchasing Power Parity", which consists of the Gross Domestic Product, in international dollars, with a view to the comparative possibility of these economies by purchasing power parity (PPP). Other sources of information were considered as objects of analysis and observations, including the statistical series of secondary data from the International Labor Office (ILO), the International Monetary Fund (IMF), the United Nations (UNDP), the Brazilian Institute of Geography and Economics (IBGE), the Department of Statistics and Socioeconomic Studies (DIEESE) and the Institute of Economic and Applied Research (IPEA). The research was conducted at the macroeconomic level of the countries, with a longitudinal temporal cut between the years 2007 and 2013, in order to observe the behavior of these economies, including during the period of the 2008 global crisis. evolution of the historical series of GDP, revealing the size of the economy, GDP per capita, which captures wealth in relation to the population. Finally, we consider the labor productivity factor itself, which deals with the relationship between GDP, the number of people and the number of hours worked in the period. This research has as general objective to identify the variables or contributing factors to subsidize the discussion about reduction of the Working Day. As a specific objective, what is proposed is to verify how these same variables affect Productivity. For both objectives the macroeconomic aspects of the countries analyzed are considered. The criterion for selecting these countries is based on the "ranking" of the OECD and World Bank database for the year 2013, considering all the major world economies, which together represent 65.22% of global GDP. The data extracted refer to the "Gross Domestic Product - GDP at (PPP) - Purchasing Power Parity", which consists of the Gross Domestic Product, in international dollars, with a view to the comparative possibility of these economies by purchasing power parity (PPP). Other sources of information were considered as objects of analysis and observations, including the statistical series of secondary data from the International Labor Office (ILO), the International Monetary Fund (IMF), the United Nations (UNDP), the Brazilian Institute of Geography and Economics (IBGE), the Department of Statistics and Socioeconomic Studies (DIEESE) and the Institute of Economic and Applied Research (IPEA). The research was conducted at the macroeconomic level of the countries, with a longitudinal temporal cut between the years 2007 and 2013, in order to observe the behavior of these economies, including during the period of the 2008 global crisis. evolution of the historical series of GDP, revealing the size of the economy, GDP per capita, which captures wealth relative to the population. Finally, we consider the labor productivity factor itself, which deals with the relationship between GDP, the number of people and the number of hours worked in the period. Design/Methodology/ approach – The method is a qualitative research of the exploratory type, subsidized by quantitative correlation analysis, and the statistical design is directed to the verification of the degree of association between the variables: Working day and Labor productivity; that is, calculation and interpretation of the degree of correlation between these two variables. Findings – In the final conclusion of the study, it is inferred based on the theoretical reference and the analysis of the statistical data, if the reduction in the working day contributes to changes in productivity indexes, and just as other variables are considered in this discussion. Research limitations – No aspects of the national culture, climatic conditions and segregation of nations by percentage of participation in agriculture, industry, and services were considered in the composition of their economies, with a view to performing comparative analysis by subgroups. In addition, the sample set is restricted both in number of countries and in relation to the relatively short period between 2007 and 2013, in addition to being marked by an atypical event such as the global economic crisis of 2008. Practical contributions – To governments, organizations and workers to rethink the possible economic and social benefits, through public policies that allow greater flexibility in working hours, focusing on the competitive advantages and the balance of the relation between labor and capital, observing the legal aspects, productivity, quality of life, unit costs and the generation of jobs / Esta pesquisa tem como objetivo geral identificar as variáveis ou fatores contribuintes para subsidiar a discussão sobre redução da Jornada de Trabalho. Como objetivo específico, o que se propõe é verificar como essas mesmas variáveis afetam a Produtividade. Para ambos os objetivos são considerados os aspectos macroeconômicos dos países analisados. O critério para seleção desses países se fundamenta no “ranking” da base de dados da Organização para a Cooperação e Desenvolvimento Econômico – OCDE e do Banco Mundial, ano base 2013, considerando-se o conjunto das maiores economias mundiais, que, juntas, representam 65,22% do PIB global. Os dados extraídos são referentes ao “Gross Domestic Product – GDP at (PPP) - Purchasing Power Parity”, que consiste no Produto Interno Bruto, em dólares internacionais, com vistas à possibilidade comparativa destas economias pela paridade do poder de compra (PPC). Outras fontes de informações foram consideradas como objetos de análise e observações, incluindo-se as séries estatísticas de dados secundários do Instituto Internacional do Trabalho (OIT), do Fundo Monetário Internacional (FMI), das Nações Unidas (UNDP), do Instituto Brasileiro de Geografia e Economia (IBGE), do Departamento Intersindical de Estatística e Estudos Socioeconômicos (DIEESE) e do Instituto de Pesquisa Econômica e Aplicada (IPEA). A pesquisa foi conduzida no nível macroeconômico dos países, com corte temporal longitudinal entre os anos de 2007 a 2013, com o objetivo de observar-se o comportamento dessas economias, inclusive durante o período da crise mundial de 2008. Nesse sentido, foi avaliada a evolução da série histórica do PIB, como reveladora do tamanho da economia, o PIB per capita, que captura a riqueza em relação à população. Por último, considera-se o fator produtividade do trabalho propriamente dito, que trata da relação entre o PIB, o número de pessoas e o número de horas trabalhadas no período. Quanto ao método, trata-se de pesquisa qualitativa do tipo exploratória, subsidiada por análise quantitativa correlacional, sendo o delineamento estatístico direcionado para a verificação do grau de associação entre as varáveis: Jornada de trabalho e Produtividade do trabalho; ou seja, cálculo e interpretação do grau de correlação entre essas duas variáveis. Na conclusão final do trabalho, infere-se com base no referencial teórico e na análise dos dados estatísticos, se a redução na jornada de trabalho contribui para alterações nos índices de produtividade, e assim como outras variáveis são consideradas nesta discussão. Não foram considerados aspectos da cultura nacional, condições climáticas e segregação das nações por percentual de participação respectivamente em agricultura, indústria, e serviços, na composição de suas economias, visando realizar análise comparativa por subgrupos. Além disto o conjunto amostral é restrito, tanto em número de países, quanto em relação ao período, relativamente curto, entre 2007 e 2013, além de ter sido marcado por fato atípico como a crise econômica mundial de 2008. Á governos, organizações e trabalhadores para repensarem os eventuais benefícios econômicos e sociais, através de políticas públicas que permitam maior flexibilização das jornadas de trabalho, com foco nas vantagens competitivas e no equilíbrio da relação entre mão de obra e capital, observando os aspectos legais, a produtividade, a qualidade de vida, os custos unitários e a geração de empregos

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