Дисертації з теми "PEG HYDROGEL"
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Phelps, Edward Allen. "Bio-functionalized peg-maleimide hydrogel for vascularization of transplanted pancreatic islets." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/45899.
Повний текст джерелаRohn, Mathias. "Strukturcharakterisierung photochemisch vernetzter tetra-PEG Hydrogele mit unterschiedlichem Aufbau." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-229602.
Повний текст джерелаWeber, Laney M. "Biologically active PEG hydrogel microenvironments for improving encapsulated beta-cell survival and function." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3256423.
Повний текст джерелаPatterson, Patrick Branch. "Creation of a Mechanical Gradient Peg-Collagen Scaffold by Photomasking Techniques." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1384720879.
Повний текст джерелаÖberg, Hed Kim. "Advanced polymeric scaffolds for functional materials in biomedical applications." Doctoral thesis, KTH, Ytbehandlingsteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-139944.
Повний текст джерелаQC 20140116
Oborná, Jana. "Řízené uvolňování léčiv z biodegradabilních hydrogelů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-385283.
Повний текст джерелаWestergren, Elisabeth. "Analysis of hydrogels for immobilisation of hepatocytes (HepG2) in 3D cell culturing systems." Thesis, Linköpings universitet, Teknisk biologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-145392.
Повний текст джерелаBellat, Vanessa. "Ingénierie d'un nouveau nanobiohybride à base de nanorubans de titanates pour la médecine régénérative." Thesis, Dijon, 2012. http://www.theses.fr/2012DIJOS056/document.
Повний текст джерелаThis research work is devoted to new nanohybrid engineering composed of titanate nanoribbons for regenerative medicine. Over a first phase, nanoribbons were synthesized by hydrothermal treatment and their morphological, structural and chemical features were defined. A fine characterization by means of different techniques of transmission electron microscopy mainly enabled to determine their thickness; dimension which had never been measured so far. Subsequently, titanate nanoribbons were functionalized by different home-made heterobifunctional PEG. Those polymers present at one of their extremities specific functional groups being able to couple with numerous biological molecules. Some collagen type peptides containing cellular recognition sites were grafted onto those extremities. The so-formed nanobiohybrid will permit cellular adhesion and proliferation favouring in fine tissue healing and regeneration. To evaluate new nanohybrid biological properties, titanate nanoribbons cytoxicity and aggregating power were determined by MTT tests, performed on two cell populations (fibroblasts and cardiomyocytes) and platelet aggregation tests (human blood). Finally, when used to promote healing process, the new nanobiohybrid was formulated in the form of sodium alginate hydrogel permitting a direct application on damaged tissues. To confirm the interest of this galenic form, initial in vivo tests were realized
Worrell, Kevin. "Chemical and mechanical characterization of fully degradable double-network hydrogels based on PEG and PAA." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48985.
Повний текст джерелаFeliciano, Danielle Ferreira. "Cinética de formação do hidrogel de polivinil álcool - polietileno glicol (PVAl-PEG) para a reparação de cartilagem articular." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263577.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-18T02:56:18Z (GMT). No. of bitstreams: 1 Feliciano_DanielleFerreira_M.pdf: 2215803 bytes, checksum: 78c936869613a6b313b028d4e7b84078 (MD5) Previous issue date: 2011
Resumo: Defeitos, doenças e acidentes que acometem a cartilagem articular para suportar às constantes solicitações mecânicas que estas regiões estão sujeitas, sendo indicada a utilização de estruturas viscoelástica resistente alto grau de atrito para preencher tais defeitos. Desta forma, foi selecionado o uso de hidrogéis para esta aplicação específica. Hidrogéis a base de poli(álcool vinilico) (PVAl) e polietileno glicol (PEG) apresentam propriedades mais adequadas, como biocompatibilidade, não estimulando reação imunológica ao organismo; baixa adesão de células sanguíneas, evitando coágulos; capacidade de absorção de água (intumecimento), proporcionando lubrificação do material e alto grau de transparência. O processo para obtenção desta blenda e formação de hidrogel foi realizado utilizando uma proporção de 1:9 (PEG:PVAl). O iniciador 2- hidroxi-4'-(2-hidroxietoxi)-2-metilpropiofenona foi adicionado à blenda, em 1% do volume total. È este iniciador, quando estimulado via temperatura, laser ou infravermelho, que irá desencadear as ligações intermacromoleculares de PEG-PVAl permitindo a formação de uma organização grafitizada da blenda dentro do hidrogel. Foi acompanhada a cinética de formação deste hidrogel através de reometria de placas, Espectroscopia de Infravermelho por Transformada de Fourier (FTIR) e Calorimetria Diferencial de Varredura (DSC). As amostras também foram devidamente caracterizadas quanto à condutividade térmica, densidade e absorção óptica. Observou-se que o iniciador ativou as ligações do grupo acetato do PVAl com as hidroxilas do PEG, resultando em formação de grupos ester. São estas ligações que caracterizam a formação do hidrogel grafitizado. Além disso, ocorreu a inversão do módulo viscoso em relação ao módulo de elasticidade, comprovando a reação de grafitização
Abstract: Defects, diseases and accidents that affect the articular cartilage can withstand constant mechanical stresses that they are subject, which indicated the use of viscoelastic structures resistant to high friction to fill these defects. In this way, the use was selected of hydrogels for this application it specifies. To base of I polished hydrogels polyvinyl alcohol (PVA) and polyethylene glycol (PEG) present more appropriate properties, biocompatibility, not stimulating reaction immunologically to the organism; low adhesion of blood cells, avoiding clots; capacity of absorption of water (swelling), providing lubrication of the material and high degree of transparency. The process for getting this blend and formation of hydrogel was carried out using a proportion of 1:9 (PEG:PVA). The initiator hidroxi 2-hidroxi-4 '-(2-hidroxietoxi)-2- metilpropiofenona was added to the blend, in 1 % of the total volume. This initiator, when stimulated he was seeing temperature, laser or infrared, what will be going to unleash the connections intermacromoleculares of PEG-PVA allowing the formation of an grafiting organization of the blend inside the hydrogel. There was accompanied the kinetic one of formation of this hydrogel through parallel plates rheometry, Fourier transform infrared spectroscopy (FTIR) and Differential scanning calorimetry (DSC). The samples also were characterized property as for the thermal condutivity, density and optical absorption. It noticed to itself that the initiator activated the connections of the group acetate of the PVA with the hydroxyl group of PEG, when ester is turning in formation of groups. It is these connections that characterize the formation of the hydrogel grafiting. Besides, it took place to inversion of the viscous module regarding the module of elasticity, proving the reaction of grafiting
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
Gramm, Stefan. "Thermisch schaltbare Hydrogele - Synthese - Charakterisierung - Anwendung." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1163522282581-78351.
Повний текст джерелаDilla, Rodger Alan. "Poly(ethylene glycol)-based Polymers: Synthesis, Characterization, and Application." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555344606484453.
Повний текст джерелаMinier, Nicolas. "Development of an organ-on-chip microfluidic device incorporating an actuatable hydrogel layer to produce barrier tissue mimicries on chips." Thesis, Compiègne, 2021. https://bibliotheque.utc.fr/Default/doc/SYRACUSE/2021COMP2644.
Повний текст джерелаModern day ethics and laws call for more safety and use of fewer animals in biomedical research. It became crucial to develop novel in vitro devices of higher relevance. Since the end of the twentieth century, several systems have been proposed by researchers in attempts to palliate the shortcomings of current systems. Notably, organs-on-chip systems are specifically tailored to recapitulate tissue functions in a manner that remains easily accessible for the experimenter. Despite the significant improvements that were brought during the last century to in vitro cell and tissue culture systems, the field of bioengineering is still young and much progress remains to be done. The work presented here details the development of an organ-on-chip that includes a biocompatible and actuatable hydrogel membrane, with controlled physico-chemical properties. Such chip is relevant when hosting barrier tissues, which are composed of several cell types, disposed on each side of a barrier, as well as within its bulk, and are often submitted to mechanical stimuli. During this PhD, several objectives have been attained. Notably, we: - Designed and produced an organ-on-chip including a biocompatible and actuatable hydrogel layer, as well as a microfluidic system allowing the independent control of both flow and actuation. - Characterized the deformation of the hydrogel layer. - Cultured intestinal cells within the chip, which formed a three dimensionally structure epithelium, and characterized its apparent permeability to molecules of varying sizes
Kanjickal, Deenu George. "Perivascular Drug Delivery Systems for the Inhibition of Intimal Hyperplasia." University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1133715441.
Повний текст джерелаVan, Scoy Bryan Richard. "A Mathematical Model for Hydrogen Production from a Proton Exchange Membrane Photoelectrochemical Cell." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1326217817.
Повний текст джерелаEndres, Kevin J. "Mass Spectrometry Methods For Macromolecules: Polymer Architectures, Cross-Linking, and Surface Imaging." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1553096604194835.
Повний текст джерелаMcPherson, Rebecca Leann. "Model of T Lymphocyte Response to Low Modulus PEG Hydrogels." Thesis, University of the Sciences in Philadelphia, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10294817.
Повний текст джерелаCardiovascular disease continues to be the leading cause of morbidity and mortality in the US and worldwide. Traditional treatments include vascular surgeries, such as angioplasty, stent placement, and vascular graft or vascular reconstruction. Of importance for this dissertation are the outcomes following vascular graft surgeries. More than 50% of vascular grafts fail within the first few years due to maladaptive responses, such as inflammation. There is a critical need to develop improved treatments to the traditional grafting procedures. One proposal to enhance outcomes is the use of cellularized, low modulus, synthetic poly(ethylene) glycol (PEG)-based biomaterials. PEG-based hydrogels have been shown to support the 3D growth and differentiation of vascular cells and may provide structural support for the vessel. A principal concern is that a growing percentage of individuals contain anti-PEG antibodies, including IgG antibodies. T cells are mediators of antibody production and play a major role in angiogenesis and in the development of arthrosclerosis. Therefore, studies to elucidate the T cell-PEG matrix interactions are needed to control and predict maladaptive responses. Here, an established murine D10-IL2, Th2 cell line, was used as a model of T lymphocyte activity to: 1) better understand the influence of PEG on T cell metabolism; 2) determine the consequence of an acute Th2 inflammatory microenvironment on the expression of pro-inflammatory responses in fibroblasts within the 3D matrix; and 3) investigate antigen presenting cell (APC)-independent T cell activation. This research demonstrated that Th2 cells experience a reversible suppression of mitochondrial membrane potential (ΔΨm) upon initial exposure to PEG. Data also suggested that T cells were susceptible to APC-independent activation during contact with the PEG matrix, as measured by an increase in IL4 and IL10 expression and the production of inflammatory cytokines (IGFBP-3, CTACK, MIP2, LIX). Additionally, this research led to the development of a bio-degradable PEG-based hydrogel system. This allowed for the investigation of aortic fibroblast cell responses to an acute inflammatory 3D microenvironment and demonstrated that the hydrogel system provided a limited protective barrier during inflammation. This research has public health benefits and has provided an improved understanding of the immunogenic nature of PEG.
Bibi, Nurguse. "Elastase responsive hydrogel dressing for chronic wounds." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/elastase-responsive-hydrogel-dressing-for-chronic-wounds(f2a1f950-d38d-4cb2-8b8e-3c1e10ef7910).html.
Повний текст джерелаHuo, Hongguang. "Tailored cell attachment and cytotoxicity in PEG-based polysaccharide-derivatized hydrogels." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 117 p, 2007. http://proquest.umi.com/pqdlink?did=1253510481&Fmt=7&clientId=79356&RQT=309&VName=PQD.
Повний текст джерелаGojela, Ntombekaya. "Hydrogen economy : MEA manufacturing for PEM electrolysers." Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/1483.
Повний текст джерелаNavarro, Flores Elisa. "Development of Ni-based electrocatalysts for hydrogen production in a PEM-type hydrogen generator." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82622.
Повний текст джерелаBuxton, Amanda Nicole. "DESIGN AND CHARACTERIZATION OF PHOTOPOLYMERIZABLE SEMI-INTERPENETRATING NETWORKS FOR IN VITRO CHONDROGENESIS OF HUMAN MESENCHYMAL STEM CELLS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=case1181591308.
Повний текст джерелаPatel, Dhaval Pradipkumar. "Novel PEG-elastin copolymer for tissue engineered vascular grafts." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45811.
Повний текст джерелаJanon, Akraphon, and s2113730@student rmit edu au. "Wind-hydrogen energy systems for remote area power supply." RMIT University. Aerospace, Mechanical & Manufacturing Engineering, 2010. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20100329.094605.
Повний текст джерелаLin, Lin. "Engineering poly (ethylene glycol) hydrogels to regulate smooth muscle cell migration and proliferation." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1401711613.
Повний текст джерелаRamos, Paja Carlos Andrés. "Fuel cell modelling and control for hydrogen consumption optimization." Doctoral thesis, Universitat Rovira i Virgili, 2009. http://hdl.handle.net/10803/8467.
Повний текст джерелаSe propone un modelo de FC basado en ecuaciones electroquímicas para predicción del exceso de oxígeno y de la temperatura de la pila, permitiendo además una conexión circuital con la carga. Así mismo, se presenta una técnica de modelado basada en Fuzzy, orientada a la emulación, obteniendo gran precisión con carga computacional reducida. Usando este último modelo se diseña e implementa un emulador. Estos modelos y el sistema de emulación fueron validados usando un sistema experimental.
Adicionalmente, diferentes topologías de sistemas de potencia basados en FC se proponen y analizan, obteniendo un criterio de selección dependiendo de la aplicación. Así mismo, se presentan criterios de control para una operación segura y eficiente del sistema. Finalmente, se proponen una metodología para la caracterización de los puntos óptimos de operación, y una estructura de control para operar en esas condiciones óptimas, siendo validados en un sistema experimental representativo del estado del arte.
in English:
A new FC modeling approach based on electrochemical equations for thermal and oxygen excess ration prediction with a circuit-based load connection is introduced. A fuzzy-based modeling technique is also proposed for emulation purposes, it reproducing the fuel cell dynamics with a high accuracy and a short computational time. The implementation of a fuel cell emulation system, based on this model, is described and analyzed. The models and the emulation system are experimentally validated by using a benchmark fuel cell system.
Different topologies for fuel cell-auxiliary storage devices interaction are also proposed and analyzed, thus giving an architecture selection criterion based on the load profile. Controllers, dynamic constrains and control objectives are designed for a safe and efficient fuel cell operation. Finally, a methodology for the identification of the fuel cell optimal operation conditions has been proposed, and a control strategy for operating in that optimal profile is introduced and validated.
Goh, Wei Chiun. "Hybrid hydrogen energy stored in stand-alone power system." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/578.
Повний текст джерелаRohn, Mathias [Verfasser], Brigitte [Akademischer Betreuer] Voit, and Sebastian [Gutachter] Seiffert. "Strukturcharakterisierung photochemisch vernetzter tetra-PEG Hydrogele mit unterschiedlichem Aufbau / Mathias Rohn ; Gutachter: Sebastian Seiffert ; Betreuer: Brigitte Voit." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://d-nb.info/1142736342/34.
Повний текст джерелаRoos, Warren C. "Modeling and Analysis of Air Breathing Hydrogen-Based PEM Fuel Cells." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1302184046.
Повний текст джерелаCampana, Alex. "Analisi tecnico-economica di configurazioni di impianto Power to Hydrogen per uso industriale." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Знайти повний текст джерелаDavila, Ramos Johanna. "Syntheses and uses of modified polyelectrolytes for therapeutic hydrogels and films with controlled and selective protein adsorption." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAF005/document.
Повний текст джерелаThe first part of this thesis is dedicated to the modification of polyelectrolytes to form polyelectrolyte films with controlled and stretch responsive cell and protein adsorption properties. Poly(acrylic acid) (PAA) was modified with side phosphorylcholine groups (PC) at rates of 25 % or with oligo(ethylene oxide) chains ended by biotin ((EO)nBiotin, (n =0, 3, 9 and 18) at 1, 5, 10 and 25 % modification rates. Polyelectrolytes multilayer films (PEM) containing these polyelectrolytes bind selectively streptavidin but repel all other proteins. The adsorption properties and selectivity were measured by quartz crystal microbalance. On a stretchable PDMS substrate, we have built PEM ended by PAA bearing RGD, covered by two PAA-PC layers on the top. Under rest, only the PC groups are exposed and prevent cell adhesion; when the film is stretched, the underlying RGD groups are exposed, and trigger adhesion of fibroblasts.The second part was consecrated to the study of poly(methacrylic acid) hydrophobically modified with alkyl chains connected through an ester moiety to the main chain. Three different chains were grafted -C12H25; -C18H35 and -C4H8- OOC-C11H23 with a rate of 1, 5 and 10 %. These polymers associate in water and form hydrogels in physiological buffer, for modification rates higher than 5 % and polymer concentrations higher than 4 wt. %. The gels were characterized by rheology. Their incubation with lipases resulted in a decrease of their viscosity, which could be interpreted by the cleavage of the hydrophobic side chains, by rheological tests. When the gels with PAA-C12 were incubated with a culture of Pseudomonas aeruginosa, their viscosity decreased, which shows that alkyle chains are also cleaved in vivo
Poveda, Reyes Sara. "Protein-based injectable hydrogels towards the regeneration of articular cartilage." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/61392.
Повний текст джерела[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
[CAT] 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 no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61392
TESIS
Premiado
Hagel, Valentin [Verfasser], and Joachim P. [Akademischer Betreuer] Spatz. "Struktur-Funktions-Korrelationen in PEG-DA- und Hyaluronsaeure-Hydrogelen / Valentin Hagel ; Betreuer: Joachim P. Spatz." Heidelberg : Universitätsbibliothek Heidelberg, 2013. http://d-nb.info/1177381699/34.
Повний текст джерелаOttosson, Anton. "Integration of Hydrogen Production via Water Electrolysis at a CHP Plant : A feasibility study." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-83717.
Повний текст джерелаNardella, Michele. "Cardiopatch impiantabili e idrogel iniettabili per il trattamento dell’infarto miocardico." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Знайти повний текст джерелаRossi, Gianmarco. "modeling of proton exchange membrane water electrolyzer for green hydrogen production from solar energy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Знайти повний текст джерелаMarthosa, Sutida. "Improvement of electrocatalyst performance in hydrogen fuel cells by multiscale modelling." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/improvement-of-electrocatalyst-performance-in-hydrogen-fuel-cells-by-multiscale-modelling(534c4857-865e-4759-a44f-e1639e4eaa1b).html.
Повний текст джерелаTazzari, V. "SINTESI DI NUOVE MOLECOLE PER IL TRATTAMENTO DI PATOLOGIE INFIAMMATORIE." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/170506.
Повний текст джерелаSpeccher, Alessandra. "Tissue engineering approaches for brain injury applications." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/262798.
Повний текст джерелаSpeccher, Alessandra. "Tissue engineering approaches for brain injury applications." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/262798.
Повний текст джерелаRhandi, Maha. "Modélisation de procédés électrochimiques de type PEM (Proton Electrolyte Membrane) pour le développement du vecteur Hydrogène." Thesis, Université Grenoble Alpes, 2021. http://www.theses.fr/2021GRALI008.
Повний текст джерелаCurrently, hydrogen is considered as a promising energy carrier. However, it needs to be produced first using electrolysis, photo catalysis, thermochemical or biological processes. Then hydrogen is stored by compression, liquefaction, physisorption or chemisorption. Lastly, the conversion process occurs, which is based on using it as a product or a reactant in an application like Fuel Cells. Hydrogen fulfils the main characteristics to achieve the performance required for efficient energy carrier, but its low volume density remains a weak point. An extremely high energy-efficient compression is a necessary step. On the other hand, hydrogen purification step is also essential for several applications as mobility.The aim of this work is to investigate the Polymer Electrolyte Membrane (PEM) devices for hydrogen energy carrier. Specifically, PEM Water Electrolysis (PEMWE) for hydrogen production and Electrochemical Hydrogen Compressor/Concentrator (EHC) for hydrogen storage. First, a preliminary study was carried out using a dimensionless analytical steady state model of PEM electrolysis cells operating with large pressure gradient. This approach enables the estimation of performance using three dimensionless parameters that governed the electrochemical reaction at the catalyst layer and the mass transport through the membrane. The dimensionless numbers are: (i) a Wagner like numbers at the anode and cathode side which is the ratio between the protonic conductivity and the electrochemical kinetic at the catalyst layer, (ii) a number similar to Thiele modulus at the catalyst layers that describes the effective protonic conductivity and the operational current density, (iii) a dimensionless ratio describing the water transport process through the membrane. The model was applied to the PEMWE and it was in good agreement with the experimental data. Secondly, hydrogen compression and purification experiments were conducted using an EHC. During these tests, the compression was performed between 0 and 30 bars for different temperatures and relative humidity. In addition, an electrochemical impedance spectroscopy (EIS) measurement was also performed. These experiments ran on both pure hydrogen and hydrogen/nitrogen mixture. After the data entropy analysis and the postmortem characterization using FTIR and SEM imaging it was found that the azote is not a benign component for this application. Surprisingly, the N2 can lead to the degradation of the membrane due to local NH3 synthesis. Finally, an electrochemical impedance spectroscopy (EIS) model was developed. The EIS is a strong characterization method which inclines both theoretical and experimental approaches by modelling the different physics and electrochemical process into a very complexed system. The one-dimensional analytical model describes the electrochemical kinetics of the cell in EIS regime. This method allows to highlight the limiting process and to predict the artefacts
Appressi, Lorenzo. "Biogas and bio-hydrogen: production and uses. A review." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9071/.
Повний текст джерелаGuan, Tingting. "Biomass-fuelled PEM FuelCell systems for small andmedium-sized enterprises." Doctoral thesis, KTH, Energiprocesser, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176633.
Повний текст джерелаQC 20151109
Rice, Mark Andrew. "PEG-based hydrogels as chondrocyte carriers for tissue engineered cartilage: Controlling extracellular matrix evolution and integration with native cartilage." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3207731.
Повний текст джерелаJurečka, Radek. "Možnosti využití vodíku v letectví." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-234197.
Повний текст джерелаAlex, Ansu. "Tidal stream energy integration with green hydrogen production : energy management and system optimisation." Thesis, Normandie, 2022. http://www.theses.fr/2022NORMC216.
Повний текст джерелаThe overarching aim of this thesis is to design, implement and compare different energy management strategies and optimisation approaches for a hybrid system involving floating tidal stream energy integration with green hydrogen production. Towards reaching the objectives, the individual system components are modelled initially. The annual system performance capabilities of the tidal stream energy plant are then obtained using frequently occurring daily profiles at the Fall of Warness berth in the Orkney Islands, Scotland. The transitionary operating modes of two polymer electrolyte membrane electrolyser units, when subjected to the energy from the tidal stream plant are analysed based on a rule-based approach energy management strategy. Later, a preliminary evaluation of the hydrogen production cost is assessed based on different daily hydrogen demand and daily tidal profile conditions. Further, an optimisation approach with the objective to maximise the system operating profit ensuring optimal and sufficient operations of both the electrolyser units under real system constraints, is formulated with priority for tidal energy powered hydrogen production. The optimisation problem is solved using a genetic algorithm based on the mixed integer non-linear problem. A comprehensive cost-benefit analysis based on fixed-variable costs and levelised costs factors is performed to analyse the optimal techno-enviro-economic operation of a hybrid grid connected tidal-wind-hydrogen energy system. The outcomes are compared against the rule-based approach results. The annualised profits in the optimisation approach are estimated to be 41.5% higher compared to the rule-based approach. Further, from an environmental view, the best optimisation results are approximately 47% higher than the rule-based approach results in terms of carbon emission reductions. A dynamic electrolyser capable of working at twice of its nominal power rating for limited duration, resulted particularly advantageous when coupled with tidal energy which is cyclic in nature with predictable periods of high and low power generation. Finally, it was determined that the fixed cost (FC) optimisation approach is relatively simple in terms of cost estimation. On the contrary, while the levelised cost (LC) approach yields slightly better results, it necessitates a greater prior knowledge of system operations to reasonably estimate the cost factors. The proposed method can be used as a generic tool for electrolytic hydrogen production analysis under different contexts, with preferable application in high green energy potential sites with constrained grid facilities
Uluoglu, Arman. "Solar-hydrogen Stand-alone Power System Design And Simulations." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611884/index.pdf.
Повний текст джерелаCHINESE, TANCREDI. "EXPERIMENTAL TEST AND MODELLING OF PERFORMANCE DEGRADATION OF HT-PEM FUEL CELLS FOR USE IN MICRO-CHP SYSTEMS." Doctoral thesis, Università degli Studi di Trieste, 2018. http://hdl.handle.net/11368/2920074.
Повний текст джерелаJahagirdar, Anant. "SOLAR DRIVEN PHOTOELECTROCHEMICAL WATER SPLITTING FOR HYDROGEN GENERATION USING MULTIPLE BANDGAP TANDEM OF CIGS2 PV CELLS AND TH." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3505.
Повний текст джерелаPh.D.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Materials Science and Engineering
Shevock, Bryan Wesley. "System Level Modeling of Thermal Transients in PEMFC Systems." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/31079.
Повний текст джерелаMaster of Science