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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.
51

Reciclagem de resíduos industriais na fabricação de argamassas e placas cerâmicas premoldadas fabricadas a partir de matriz sílico-aluminosa destinadas a construção civil / Recycling of industrial residues in the manufacture of mortars and premolded ceramic plates manufactured from matrix silico aluminoso destined to civil construction

CARVALHO, Ronaldo Nonato Ferreira Marques de 05 1900 (has links)
Submitted by Nathalya Silva (nathyjf033@gmail.com) on 2017-04-24T20:10:58Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ReciclagemResiduosIndustriais.pdf: 6864322 bytes, checksum: 812fe47d1e2986d41b67f7534c9e8955 (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-04-26T15:08:37Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ReciclagemResiduosIndustriais.pdf: 6864322 bytes, checksum: 812fe47d1e2986d41b67f7534c9e8955 (MD5) / Made available in DSpace on 2017-04-26T15:08:37Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ReciclagemResiduosIndustriais.pdf: 6864322 bytes, checksum: 812fe47d1e2986d41b67f7534c9e8955 (MD5) Previous issue date: 2014-05 / Propõe-se à fabricação de placas estruturadas com trama de dutos em PVC, preenchidas com argamassa composta por materiais rejeitados da construção civil, além de cinzas volantes de carvão mineral, da Cal hidratada e cimento Portland, inspiradas na técnica tradicional da taipa-de-mão empregada no Estado do Pará. O produto final é um sistema construtivo contemporâneo e ecológico, destinado a execução de painéis divisórios, tendo por objetivo a redução residual e o reaproveitamento de materiais rejeitados, cujo descarte acarreta danos ambientais. Os rejeitos apresentam características físico-químicas que permitem sua reciclagem, aumentando a duração de seu ciclo de vida. Visando desenvolver material argamássico, tendo como características a plasticidade, a elasticidade e a resistência mecânica, foram realizados experimentos com traços compostos pelos rejeitos e cimento Portland devidamente processados e dosados para a confecção de corpos de prova. Estes foram submetidos aos ensaios de absorção de água, porosidade aparente, massa específica aparente e resistência à compressão, resultando na seleção do composto mais adequado, no que se refere a utilização no fabrico de placas cerâmicas taipadas, montáveis para uso em painéis divisórios. As placas foram submetidas aos ensaios de compressão e tração. / It is proposed to manufacture plates in structured network of PVC pipes, filled with mortar composed of rejected materials of civil construction, and coal fly ash, hydrated lime and Portland cement, inspired by the traditional technique of earth construction called “taipa de mão”, employed in the State of Pará, Brazil. The final product is a contemporary and ecological construction system for the execution of partition panels, aiming the decrease and the reuse of waste construction’ materials, whose disposal causes environmental damage. The rejected materials have physical-chemical characteristics which allow its recycling, increasing the duration of their Life Cycle. Aiming to develop mortar’s material having characteristics as plasticity, elasticity and mechanical strength were made experiments with traces consisting of construction waste and Portland cement, duly processed and dosed for the confection of test bodies. These were submitted to the tests absorption of water, porosity, density, compressive strength and toughness, resulting in the selection of the most appropriate compound, in respect to use in manufacturing mountable ceramic plates for use in partition panels. The plates were submitted to the tests of compression and tension.
52

Diagnóstico e sugestões de melhoria da gestão dos resíduos de construção e demolição (RCD), na área urbana de Boa Vista/RR /

Chitlal, Ítalo Harry Cunha January 2019 (has links)
Orientador: Paulo Valladares Soares / Resumo: Os Resíduos da Construção e Demolição (RCD) são um grande problema da maioria das cidades brasileiras, nos aspectos ambiental, social e econômico. Esse problema também se destaca em Boa Vista, capital e maior cidade do estado de Roraima, com aproximadamente 63% da população estadual, onde os RCD representam quase 46% do total em massa de resíduos depositados no aterro municipal. Considerando que se têm poucas informações sobre a gestão de RCD na cidade, pois o Plano Municipal de Gestão Integrada de Resíduos Sólidos (PMGIRS) de Boa Vista ainda está em fase de implementação, este trabalho teve como objetivo realizar um diagnóstico da atual situação e sugerir ajustes na gestão e destinação dos RCD na cidade de Boa Vista, por meio de levantamento bibliográfico e trabalho a campo com entrevistas às empresas de construção, empresas de transporte de entulho, o poder público municipal e com uma empresa de reciclagem de entulho. O diagnóstico revelou que a maioria das empresas de construção e de transporte de entulho não atende à legislação atual, por falta de fiscalização das autoridades. O poder público municipal se esforça para implementar o PMGIRS e tentar acabar com os depósitos clandestinos e obrigar as grandes geradoras a parar de despejar os RCD no aterro municipal. Foi identificado que existe uma empresa de reciclagem de entulho atuante na cidade de Boa Vista, porém, enfrenta dificuldades para se estabelecer num mercado que é pouco desenvolvido, sem incentivos e com a lei de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Construction and Demolition Waste (CDW) in the environmental, social and economic aspects are a big problem in most Brazilian cities, This problem also stands out in Boa Vista, capital and the largest city of Roraima state, with approximately 63% of state’s population, where the CDW represent almost 46% of the total mass of waste deposited in the municipal landfill. Considering that there is little information about the management of CDW in the city, because the Municipal Plan of Integrated Solid Waste Management of Boa Vista stills in implementation phase, this work aimed to diagnose the current situation and to suggest adjustments in the management and destination of the CDW in Boa Vista, through bibliographical survey and field work with interviews with construction companies, transportation companies of rubble, municipal public authorities and with a recycling company of rubble. The diagnosis revealed that most companies of construction and debris does not meet to current legislation, due to lack of supervision by the authorities. Municipal public authorities are struggling to implement the Municipal Plan of Integrated Solid Waste Management and try to stop clandestine deposits and force large generators to stop dumping CDW in the municipal landfill. It was identified that there is a recycling company of rubble in the city of Boa Vista, however, it faces difficulties to establish itself in a market that is poorly developed, without incentives and with the law of sustainab... (Complete abstract click electronic access below) / Mestre
53

A manifestação da fé em Cachoeira Paulista: o espaço sagrado da comunidade Canção Nova 1978-2011 / The manifestation of faith in Cachoeira Paulista: the sacred space of the community New Song, 1978-2011

Jefferson Rodrigues de Oliveira 29 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A geografia da religião no Brasil pós 1990, vem apresentando temas que auxiliam os geógrafos no entendimento do espaço. Para o geógrafo da religião, os estudos têm por análise a dimensão espacial da fé, no tempo e no espaço, trata-se da análise de duas categorias: o sagrado e o profano. Esta pesquisa visa como objetivo, o estudo da comunidade católica, a Canção Nova, inserida em um movimento renovador na Igreja Católica Apostólica Romana denominada Renovação Carismática Católica (RCC) em seu espaço e no tempo de fé. Torna-se necessário desenvolver a importância do sagrado no Vale do Paraíba Paulista em seus sucessivos (re) arranjos espaciais na hierópolis de Cachoeira Paulista. A interpretação dessas organizações espaciais ocorreu ao analisar os possíveis agentes modeladores no espaço: peregrinos, turistas, visitantes, comerciantes e moradores. O Espaço Sagrado e seus respectivos espaços vinculados representaram a contribuição geográfica dessa dissertação e facilitou a compreensão do homem com o divino e sua relação na dimensão econômica, a dimensão política e a dimensão do lugar. / The geography of religion in Brazil after 1990 has been presenting themes that assist geographers in the understanding of space. The geographer of religion studies by analyzing the spatial dimension of faith, in time and space. It is the analysis of two categories: the sacred and the profane. This researchs objective is the study of the catholic community, New Song, set in a renewal movement in the Roman Catholic Church called the Catholic Charismatic Renewal (CCR) in its space and time of faith. It is necessary to develop the importance of the sacred in the Vale do Paraiba Paulista at its subsequent (re) spatial arrangements in Hierópolis of Cachoeira Paulista. The interpretation of these organizations is to analyze the spatial potential modeling agents in space: pilgrims, tourists, visitors, merchants and residents. The Sacred Space and their respective spaces linked, geographically, represented the contribution of this dissertation and facilitated the understanding of man with the divine and its relation in the economic dimension, the political dimension and the dimension of the place.
54

A manifestação da fé em Cachoeira Paulista: o espaço sagrado da comunidade Canção Nova 1978-2011 / The manifestation of faith in Cachoeira Paulista: the sacred space of the community New Song, 1978-2011

Jefferson Rodrigues de Oliveira 29 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A geografia da religião no Brasil pós 1990, vem apresentando temas que auxiliam os geógrafos no entendimento do espaço. Para o geógrafo da religião, os estudos têm por análise a dimensão espacial da fé, no tempo e no espaço, trata-se da análise de duas categorias: o sagrado e o profano. Esta pesquisa visa como objetivo, o estudo da comunidade católica, a Canção Nova, inserida em um movimento renovador na Igreja Católica Apostólica Romana denominada Renovação Carismática Católica (RCC) em seu espaço e no tempo de fé. Torna-se necessário desenvolver a importância do sagrado no Vale do Paraíba Paulista em seus sucessivos (re) arranjos espaciais na hierópolis de Cachoeira Paulista. A interpretação dessas organizações espaciais ocorreu ao analisar os possíveis agentes modeladores no espaço: peregrinos, turistas, visitantes, comerciantes e moradores. O Espaço Sagrado e seus respectivos espaços vinculados representaram a contribuição geográfica dessa dissertação e facilitou a compreensão do homem com o divino e sua relação na dimensão econômica, a dimensão política e a dimensão do lugar. / The geography of religion in Brazil after 1990 has been presenting themes that assist geographers in the understanding of space. The geographer of religion studies by analyzing the spatial dimension of faith, in time and space. It is the analysis of two categories: the sacred and the profane. This researchs objective is the study of the catholic community, New Song, set in a renewal movement in the Roman Catholic Church called the Catholic Charismatic Renewal (CCR) in its space and time of faith. It is necessary to develop the importance of the sacred in the Vale do Paraiba Paulista at its subsequent (re) spatial arrangements in Hierópolis of Cachoeira Paulista. The interpretation of these organizations is to analyze the spatial potential modeling agents in space: pilgrims, tourists, visitors, merchants and residents. The Sacred Space and their respective spaces linked, geographically, represented the contribution of this dissertation and facilitated the understanding of man with the divine and its relation in the economic dimension, the political dimension and the dimension of the place.
55

Estudo da incorporação de altos teores de argila calcinada no concreto compactado com rolo / Study of the incorporation of high amounts of calcined clay in roller compacted concrete

RIBEIRO, Adriano Mendes 28 September 2010 (has links)
Made available in DSpace on 2014-07-29T15:03:31Z (GMT). No. of bitstreams: 1 adriano mendes.pdf: 4708776 bytes, checksum: 4bc099a31f3941241f5dd5294da28bba (MD5) Previous issue date: 2010-09-28 / The rolled compacted concrete (RCC) is a still relatively new technique, but with growing volume of use, a fact generated by its technical and economical advantages, requiring more studies in order to use with greater efficiency, safety and economy. This work deals with the RCC with high levels of replacement and addition of part of the Portland cement by calcined clay pozzolan, aiming to analyze and quantify the improvements of the concrete properties and reach a satisfactory level of use, which allows for improvement or maintenance of the properties with a lower consumption of cement per cubic meter. So its impacts on the properties of RCC for this type of mineral addition were studied for the substitution levels adopted, checking the influence on the properties of the fresh concrete in the consistency and the density. For the hardened concrete some mechanical properties and durability were evaluated by compressive and tensile strength, capillarity and immersion by water absorption, test of permeability by water and ultrasound test. The use of calcined clay come together with the needs of the cement production for the construction of dams in the north of the country, as the case of Santo Antônio / RO, because its place is far removed from major industries and cement production slag, fly ash and silica fume, requiring the study of materials to enhance the production of cement. As an important result obtained with this research, it was found that substitution ranging from 27% to 50% achieved the best results, regarding the applicability of this material on the surveyed properties. / O Concreto Compactado com Rolo (CCR) é uma técnica ainda relativamente nova, porém com volume de utilização crescente, fato gerado pelas suas vantagens econômicas e técnicas, requerendo assim mais estudos para embasar o seu uso com maior eficiência, segurança e economia. O presente trabalho trata do CCR com elevados teores de substituição e de adição de parte do volume de cimento Portland por pozolana de argila calcinada, objetivando analisar e quantificar as melhorias das suas propriedades e chegar a um teor satisfatório de utilização, o qual possibilite melhoria ou manutenção das propriedades avaliadas com um menor consumo de cimento por metro cúbico. Desta forma foram avaliados os impactos nas propriedades do CCR para este tipo de adição mineral, nos teores adotados, aferindo a influencia nas propriedades do concreto no estado fresco quanto à consistência e massa específica. No estado endurecido algumas propriedades mecânicas e de durabilidade foram analisadas através da resistência à compressão e à tração por compressão diametral, a absorção de água por capilaridade e por imersão, a permeabilidade à água e ensaio de ultrassom. O uso da argila calcinada vem ao encontro das necessidades da produção de cimento para as usinas em construção na Região Norte do país, como é o caso de Santo Antônio / RO, pois se trata de uma obra muito distante das grandes indústrias cimenteiras e da produção de escória, cinza volante e sílica ativa, o que requer a investigação de materiais para aperfeiçoar a produção de cimento. Como resultado importante obtido na pesquisa em questão, verificou-se que a substituição oscilando entre 27% a 50% atingiu os melhores resultados quanto à aplicabilidade desse material nas propriedades pesquisadas.
56

Thermal Performance of Various Roof Elements Under Different Weather Conditions

Joshi, Vijesh Vasanth January 2015 (has links) (PDF)
Beside the point of whether the country is developed or underdeveloped, energy crisis is a common scene all over the world. In order to balance energy supply and demand, either one has to increase the supply or decrease the demand. The latter seems to be the better choice since we have limited sources of energy. About 20% - 40% of energy produced by a country is being consumed by HVACs in buildings. Hence much e ort is towards energy conservation in buildings. Around 30% of the building energy consumption in India is due to cooling load. Previous studies have shown that around 60% of the heat due to solar radiation enters through the roof of the building. The present work aims to reduce the heat load entering through the roof by coming up with a better roofing technique for moderate climatic regions. In the present work, enclosures with the side walls and the floor (bottom slab) insulated has been studied both numerically and experimentally. Heat transfer between the ambient and enclosure is only through the roof (top slab). Six common roofing types have been studied in this thesis. Reinforced cement concrete (RCC) roof Mangalore tile roof Thatched roof GI Sheet roof and Concrete roof with lawn (green roof) Concrete roof with a layer of wet sand The experimental studies have been carried out to understand heat transfer through these roofs. A comparative study of all six types of roofs has been done. Apart from this, the effect of a shade net on room models with bare RCC roof and GI sheet roof is also studied and presented in this thesis. Each enclosure has a height of 0.3m and the sides are 1m in size. Mangalore tile and thatched roofs are inclined to the horizontal. To understand the heat flow process, the temperature variations of different surfaces and enclosure air, and, air temperatures near the top and bottom slabs were recorded. In addition, weather conditions such as solar radiation, ambient air temperature, and wind speed are recorded. The details of the experimental set up are given in chapter 3. In chapter 2, a mathematical model to determine the temperature variations in the enclosure is given. All the three modes of heat transfer (conduction, convection and radiation) are present and the system is unsteady. The objective is to find the temperatures of the walls and the enclosure air temperature. Heat flows either from surroundings to the enclosure or from enclosure to the surroundings through the walls of the enclosure. As the solar radiation data is known for a given location, un-steady heat conduction equation is solved for the walls of the enclosure with heat flux boundary conditions to solve for the temperatures. Standard correlations have been used for calculating the convective heat transfer to the ambient and in the enclosure. Most importantly, the experiments conducted were field experiments. The main objective of the study had been to understand the effect of roof on thermal comfort conditions inside the scaled model rooms under five different weather conditions which are commonly observed in warm tropics: (1)summer, (2)winter, (3)cloudy, (4)unsteady, and, (5)rainy. The details of weather conditions have been discussed in chapter 4. In the present analysis, various issues were looked upon such as, temperature values, time lag, thermo-physical properties of the roof material, weather conditions, average over a 24 hours cycle etc. For the comparative analysis, bare RCC roof has been assumed to the base case as most of the buildings are built with RCC roof (for example, in India, around 29% of the buildings have RCC roof, as per 2011 census). On one side we have passive cooling techniques (lawn over RCC roof and wet sand over RCC roof), and, on the other side we have breathing roofs (Mangalore tile roof and thatched roof). Apart from these, the GI sheet roof is commonly used for small scale industries and residential houses. It has been observed that the concrete roof with lawn (hereafter called as lawn over RCC roof ) being the best one among the considered six roofs. Having lawn over RCC roof could result reduction in both solar gain and the diurnal variation of enclosure inside temperatures. The range of temperature variation was least disturbed due to change in weather conditions. In the case of wet sand over RCC roof, the diurnal variations of enclosure inside temperatures were relatively higher as compared with those in the lawn over RCC roof case. As far as breathing roofs are concerned, the two were found to be better than bare RCC roof with thermal comfort as point of view. On the other hand, breathing effects are found to be better in case of Mangalore tile roof than in case of thatched roof. GI sheet roof was found to be the worst among considered for thermal comfort. The effect of using shade net over RCC and GI sheet roof proves to have good potential to reduce cooling load with negligible adverse effects during night time. Detailed discussion of results has been done in chapter 4. Numerical simulations have been carried out for the case of model room with bare RCC roof. A comparative analysis of both experimental and numerical results has been discussed in chapter 5. The important conclusions are discussed in chapter 6.
57

Einfluss des Transkriptionsfaktors B-cell lymphoma 6 (BCL6) auf die Expression renaler Transportproteine / The effect of the transcription factor B-cell lymphoma 6 (BCL6) on the expression of renal transport proteins

Millé, Aline Noel 07 November 2016 (has links)
No description available.
58

Einfluss von klarzelligen Nierenkarzinomzellen auf die immunmodulatorischen Fähigkeiten von humanen 6-sulfo LacNAc+ dendritischen Zellen

Kloß, Anja 09 September 2015 (has links) (PDF)
Nierenzellkarzinome (NZKs) gelten als stark immunogene Tumore. Dies ist insbesondere auf die Infiltration durch verschiedene Immunzellpopulationen, wie T-Lymphozyten und Natürliche Killer (NK)-Zellen, sowie das klinische Ansprechen auf immuntherapeutische Strategien zurückzuführen. Bisher existieren jedoch nur sehr wenige Studien zur Rolle von humanen nativen dendritischen Zellen (DCs) in NZK-Geweben und über die Tumor-vermittelte Modulation dieser DCs. DCs nehmen als professionelle Antigen-präsentierende Zellen eine zentrale Schlüsselrolle bei der Induktion und Aufrechterhaltung der angeborenen sowie adaptiven Immunantwort ein. Daher wurde im Rahmen dieser Arbeit erstmals der Effekt von klarzelligen NZKs auf den Phänotyp sowie die immunmodulatorischen Fähigkeiten von 6-sulfo LacNAc+ (slan)DCs evaluiert. SlanDCs, welche eine große Subpopulation humaner Blut-DCs darstellen, sind neben der Sekretion großer Mengen proinflammatorischer Zytokine dazu befähigt, Tumorzellen direkt zu lysieren. Des Weiteren sind slanDCs in der Lage, die antitumoralen Effekte von NK-Zellen zu fördern und CD4+ T-Helfer-Zellen sowie Tumor-reaktive CD8+ T-Lymphozyten effizient zu stimulieren. Angesichts dieser proinflammatorischen Eigenschaften können slanDCs wesentlich an einer Tumor-gerichteten Immunantwort beteiligt sein. Auf dieser Grundlage erfolgte im Rahmen der vorliegenden Arbeit der immunhistochemische Nachweis von slanDCs in klarzelligen NZK-Geweben. Im Vergleich zu Tumor-freiem Nierengewebe trat in den primären Tumorgeweben eine erhöhte Zahl infiltrierender slanDCs auf. Zudem wurde die Präsenz von slanDCs in Lymphknoten- sowie Fernmetastasen von NZK-Patienten beobachtet. Weiterführende Untersuchungen an frischen klarzelligen NZK-Geweben demonstrierten, dass NZK-infiltrierende slanDCs einen unreifen Phänotyp ausprägen und Interleukin-10 produzieren. Ausgehend von diesen Erkenntnissen erfolgten funktionelle Analysen, bei denen der Einfluss der kommerziell erhältlichen klarzelligen NZK-Linien ACHN und Caki-1 sowie der primären klarzelligen NZK-Linien MZ1257RC und MZ2877RC auf bedeutende immunmodulatorische Fähigkeiten von slanDCs untersucht wurde. In diesem Zusammenhang zeigte sich, dass NZK-Zellen effektiv in der Lage sind, sowohl die slanDC-vermittelte Proliferation von CD4+ und CD8+ T-Lymphozyten, als auch die slanDC-induzierte Differenzierung naïver CD4+ T-Lymphozyten in proinflammatorische T-Helfer 1-Zellen zu inhibieren. Darüber hinaus wurde demonstriert, dass NZK-Zellen das Potenzial von slanDCs zur Aktivierung von NK-Zellen hemmen. Untersuchungen der zugrunde liegenden Mechanismen zeigten, dass die funktionelle Inhibition von slanDCs durch klarzellige NZK-Zellen über membranständige Moleküle vermittelt wird. Die im Rahmen dieser Dissertation gewonnenen Erkenntnisse weisen darauf hin, dass NZKs die Ausreifung sowie wesentliche funktionelle Eigenschaften von DCs inhibieren. Dies deutet auf einen neuen Immunescape-Mechanismus klarzelliger NZKs hin, welcher auf einer Tumorzell-vermittelten Generierung von tolerogenen slanDCs basiert und eine unzureichende Aktivierung der angeborenen sowie adaptiven Tumor-gerichteten Immunantwort zur Folge hat. Diese neuen Erkenntnisse können einen Beitrag zu einem besseren Verständnis der Interaktion von NZKs mit nativen humanen DCs leisten und die Konzeption neuer therapeutischer Strategien ermöglichen, welche auf einer Verstärkung der antitumoralen Eigenschaften von DCs beruhen.
59

Repair and Retrofit Strategies for Structural Concrete against Thermo-Mechanical Loadings

Guruprasad, Y K January 2014 (has links) (PDF)
Reinforced cement concrete (RCC) structures have become an important aspect in most of the buildings in our society around the world. Most of the multistoried reinforced concrete buildings house important institutions such as hospitals, schools, government establishments, defense establishments, business centers, sports stadiums, super markets and nuclear power plants. The cost of construction of such multistoried RCC structures is very high, and these structures need to be maintained and restored based on their functionality and importance using repair and retrofit strategies when these structures undergo damage. The steps involved in restoring RCC structures that have damages using repair / retrofit measures consists of identifying the source or cause of damage, assessment of the degree or extent of damage that has taken place using nondestructive techniques. Based on the assessment of degree of damage suitable repair / retrofit strategy using the appropriate repair material is applied to achieve the required load carrying capacity or strength. The present work involves assessing the efficacy of carbon fibre reinforced polymer (CFRP) based system applied on pre-damaged structural members to restore the member’s strength and stiffness through experimental investigations and finite element predictions. To validate the macrolevel properties of predamaged concrete micromechanical analysis, microscale studies and analytical investigations have been conducted. Plain and reinforced concrete test specimens: cylinders, square prisms and rectangular prisms having 25MPa and 35MPa cylinder compressive strengths pre-damaged due to mechanical (monotonic and cyclic loading) and thermal loading (exposure to different temperature and time durations) with applications of CFRP repair subjected to compression is investigated to study the behavior and enhancement in the compressive strength and stiffness after application of repair. Non destructive testing of thermally damaged concrete (exposed to different temperature and exposure time) is conducted using ultrasonic pulse velocity and tomography methods to understand the degradation in the strength and stiffness of thermally damaged concrete. The results of the non destructive testing helps in assessing the amount of repair that can be applied. To validate the macro scale behavior of thermally damaged concrete micro scale studies was performed adopting micro indentation, petrography, Raman spectroscopy, scanning electron miscroscopy (SEM) and Electron probe micro analysis (EPMA). During the event of a fire in RC structures which have been retrofitted. The high temperature caused due to fire tends to make the concrete to deteriorate and the repair material to delaminate. Loss of strength/ stiffness in concrete and delamination of the repair material in a retrofitted structural component in a structure causes instability which results in partial collapse or complete collapse of the structure. Thermal insulation of concrete and the repair material (CFRP) using geo-polymer mortar and simwool thermal fibre blanket exposed to high temperature and different exposure time are experimentally investigated. This is to evaluate the effectiveness of the thermal insulation in protecting epoxy based structural repair material(CFRP) from thermal damage and to minimize the delamination of the repair material when exposed to high temperatures. Slender columns when loaded eccentrically fail at a load much lesser than their actual load carrying capacity. In RC buildings where additional floors need to be added, in those situations slender columns which are already eccentrically loaded tend to get damaged or fail due to additional load which act on them. Therefore to restore such columns experimental and finite element investigations on reinforced concrete slender columns having 25MPa cylinder compressive strength subjected to eccentric monotonic compressive loading with applications of CFRP repair is studied to understand the behavior and the enhancement in load carrying capacity after application of repair. Experimental investigations are conducted to study fracture and fatigue properties of thermally damaged concrete geometrically similar notched plain and reinforced concrete beams having 25MPa cylinder compressive strength exposed to different combinations of temperature and durations with application of repair (CFRP). Nonlinear fracture parameters of thermally damaged concrete is computed which help in understanding the fracture behavior of thermally damaged concrete and application of repair. Effectiveness of CFRP repair and failure behaviour of these beams are studied when these thermally damaged notch concrete beams are subjected to monotonic and cyclic (fatigue) loading. Reinforced concrete slender beams when subjected to unexpected loads such as earthquakes get damaged. The increase in load carrying capacity and fatigue life of reinforced concrete slender beams having 25MPa cylinder compressive strength in flexure subjected to monotonic and cyclic loading with applications of CFRP repair is investigated using experimental and finite element investigations. Finite element analysis of concrete specimens pre-damaged due to mechanical (monotonic and cyclic loading) / thermal loading (exposure to different temperature and time durations) with applications of CFRP repair and assessment of amount of repair required is investigated. Analytical (empirical) models are developed to assess the mechanical properties of concrete (elastic moduli, compressive strength and split tensile strength) exposed to different temperatures and time durations. Nonlinear fracture parameters of geometrically similar plain concrete notch beams exposed to different temperature and time durations are determined. Fracture parameters (stress intensity factor) of thermally damaged plain and reinforced concrete notched beams with application of CFRP have been determined. Effect of size and shape of thermally damaged plain concrete compression members with application of CFRP wrap have been studied. Crack mouth opening displacements (CMOD), strains and crack lengths of thermally damaged plain concrete (PC) notched beams using digital image correlation has also been determined.
60

Einfluss von klarzelligen Nierenkarzinomzellen auf die immunmodulatorischen Fähigkeiten von humanen 6-sulfo LacNAc+ dendritischen Zellen

Kloß, Anja 02 September 2015 (has links)
Nierenzellkarzinome (NZKs) gelten als stark immunogene Tumore. Dies ist insbesondere auf die Infiltration durch verschiedene Immunzellpopulationen, wie T-Lymphozyten und Natürliche Killer (NK)-Zellen, sowie das klinische Ansprechen auf immuntherapeutische Strategien zurückzuführen. Bisher existieren jedoch nur sehr wenige Studien zur Rolle von humanen nativen dendritischen Zellen (DCs) in NZK-Geweben und über die Tumor-vermittelte Modulation dieser DCs. DCs nehmen als professionelle Antigen-präsentierende Zellen eine zentrale Schlüsselrolle bei der Induktion und Aufrechterhaltung der angeborenen sowie adaptiven Immunantwort ein. Daher wurde im Rahmen dieser Arbeit erstmals der Effekt von klarzelligen NZKs auf den Phänotyp sowie die immunmodulatorischen Fähigkeiten von 6-sulfo LacNAc+ (slan)DCs evaluiert. SlanDCs, welche eine große Subpopulation humaner Blut-DCs darstellen, sind neben der Sekretion großer Mengen proinflammatorischer Zytokine dazu befähigt, Tumorzellen direkt zu lysieren. Des Weiteren sind slanDCs in der Lage, die antitumoralen Effekte von NK-Zellen zu fördern und CD4+ T-Helfer-Zellen sowie Tumor-reaktive CD8+ T-Lymphozyten effizient zu stimulieren. Angesichts dieser proinflammatorischen Eigenschaften können slanDCs wesentlich an einer Tumor-gerichteten Immunantwort beteiligt sein. Auf dieser Grundlage erfolgte im Rahmen der vorliegenden Arbeit der immunhistochemische Nachweis von slanDCs in klarzelligen NZK-Geweben. Im Vergleich zu Tumor-freiem Nierengewebe trat in den primären Tumorgeweben eine erhöhte Zahl infiltrierender slanDCs auf. Zudem wurde die Präsenz von slanDCs in Lymphknoten- sowie Fernmetastasen von NZK-Patienten beobachtet. Weiterführende Untersuchungen an frischen klarzelligen NZK-Geweben demonstrierten, dass NZK-infiltrierende slanDCs einen unreifen Phänotyp ausprägen und Interleukin-10 produzieren. Ausgehend von diesen Erkenntnissen erfolgten funktionelle Analysen, bei denen der Einfluss der kommerziell erhältlichen klarzelligen NZK-Linien ACHN und Caki-1 sowie der primären klarzelligen NZK-Linien MZ1257RC und MZ2877RC auf bedeutende immunmodulatorische Fähigkeiten von slanDCs untersucht wurde. In diesem Zusammenhang zeigte sich, dass NZK-Zellen effektiv in der Lage sind, sowohl die slanDC-vermittelte Proliferation von CD4+ und CD8+ T-Lymphozyten, als auch die slanDC-induzierte Differenzierung naïver CD4+ T-Lymphozyten in proinflammatorische T-Helfer 1-Zellen zu inhibieren. Darüber hinaus wurde demonstriert, dass NZK-Zellen das Potenzial von slanDCs zur Aktivierung von NK-Zellen hemmen. Untersuchungen der zugrunde liegenden Mechanismen zeigten, dass die funktionelle Inhibition von slanDCs durch klarzellige NZK-Zellen über membranständige Moleküle vermittelt wird. Die im Rahmen dieser Dissertation gewonnenen Erkenntnisse weisen darauf hin, dass NZKs die Ausreifung sowie wesentliche funktionelle Eigenschaften von DCs inhibieren. Dies deutet auf einen neuen Immunescape-Mechanismus klarzelliger NZKs hin, welcher auf einer Tumorzell-vermittelten Generierung von tolerogenen slanDCs basiert und eine unzureichende Aktivierung der angeborenen sowie adaptiven Tumor-gerichteten Immunantwort zur Folge hat. Diese neuen Erkenntnisse können einen Beitrag zu einem besseren Verständnis der Interaktion von NZKs mit nativen humanen DCs leisten und die Konzeption neuer therapeutischer Strategien ermöglichen, welche auf einer Verstärkung der antitumoralen Eigenschaften von DCs beruhen.

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