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SAITTA, CLAUDIA. « Predisposition to hematological malignancies in children and adults : from genetic profiling to clonal evolution ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/365155.
Texte intégralDespite genetic predisposition occurs in 5-10 % of pediatric cancer, it is still a nebulous field, that has to be better characterized. In the adult setting, clonal evolution acts similarly, and age-dependent accumulation of somatic mutations increases the prevalence of myeloid neoplasms among older individuals. How the specific co-occurrence of somatic events predisposes to hematological malignancies have to be further clarified. In the present project, we focused our attention in dissecting the role of genetic predisposition in both childhood and adult hematological malignancies, with the purpose of improving knowledge about genetic alterations that act in pre-leukemic phase. We planned and developed our study through several tasks, characterized by the joint purpose of investigating the contribution of genetic predisposition in promote tumor transformation. Firstly, we screened a cohort of 120 consecutive diagnosis of pediatric patients affected by Acute Lymphoblastic Leukemia and sporadic cases with other hematological malignancies, as well as cases with familiar recurrence. Genetic profiling confirmed the crucial role of some genes in Leukemogenesis, like those belonging to Ras pathway, both in term of incidence and pathogenicity. Moreover, it shed light on germline mutations in Cohesins: these alterations, usually associated to genetic syndromes called Cohesinopathies, are not random or sporadic events, but occur with a frequency (6%) that is not negligible and worthy of further study. Considering this evidence, we made a focus on STAG1 and RAD21 germline variants. Our results demonstrated that they lead to a poor chromosomal strength and promote spontaneous instability, resulting in a lowered response to exogenous and endogenous agents, as well as defective DNA repair mechanisms. So, genes that are not classically related to full-blown stage of hematological disease, promote cancer prone conditions in pediatric patients, aggravating the risk of somatic events that are responsible of the disease’ onset. In order to evaluate the contribution of genetic predisposition in cancer considering overall the time of life, we investigated the role of clonal evolution in the adult setting. Despite it is considered normal in aging, it is also significantly associated with cardiovascular disease, as well as solid tumors and hematological malignancies. The mutational screening of 1794 oldest-old individuals allowed to establish a model based on 3 risk groups, in which differential age-dependent accumulation of somatic mutations increases prevalence of myeloid malignancies or inflammatory-associated diseases. Specifically, mutations in Splicing genes, JAK2 or the presence of multiple mutations (DNMT3A, TET2, ASXL1 with additional genetic lesions), as well as variants with allele frequency ≥0.096, have a positive predictive value for myeloid neoplasms. Finally, we underlined the role of Splicing genes mutations not only as early events in pathogenesis, but also in a previous phase, as key players in determine the onset of myelodysplastic disease. Overall, a better knowledge and characterization of these alterations will have different impacts: it will improve the understanding of tumorigenesis, opening new scenarios regarding the contribution of genetic predisposition and clonal evolution to hematological malignancies. Moreover, it could have significative effects on both patients’ care and familial genetic counseling, enabling targeted surveillance strategies, and tailored therapeutical adjustments that include familiar screening in case of familiar donor in hematopoietic stem cell transplantation.
Ferreira, Renata Cristina Grangeiro. « Caracterização do complexo coesina de Trypanosoma cruzi ». reponame:Repositório Institucional da UnB, 2011. http://repositorio.unb.br/handle/10482/7981.
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A segregação das cromátides irmãs para os pólos opostos da célula durante a divisão celular é um evento complexo durante o ciclo de vida de uma célula eucariótica. Tanto na mitose quanto na meiose a coesão entre as cromátides irmãs é essencial para que ocorra a correta segregação cromossomal, evento sob a responsabilidade do complexo protéico chamado Coesina. Este complexo é melhor conhecido em leveduras e mamíferos, sendo formado por duas proteínas SMC (proteínas de manutenção estrutural dos cromossomos), SMC1 e SMC3, e duas proteínas SCC (proteínas de coesão das cromátides irmãs), a SCC1 (também conhecida como Mcd1 ou Rad21) e SCC3 (SA1 e SA2 em células de mamíferos). A coesina mantém as cromátides irmãs unidas a partir da fase S do ciclo celular e essa coesão é mantida até a transição entre a metáfase e a anáfase, quando as cromátides irmãs se separam para os pólos opostos da célula. Existem poucos estudos sobre a coesina em tripanossomatídeos e o projeto genoma mostrou a presença dos genes para todas as subunidades da Coesina em Trypanosoma cruzi, Trypanosoma brucei e a Leishmania major. Neste trabalho nós propusemos a análise da expressão e a imunocitolocalização das subunidades do complexo Coesina em T. cruzi. Anticorpo contra a subunidade TcSCC1 produzido em coelho foi utilizado em ensaios de western blot e imunofluorescência em microscopia confocal, para as formas amastigotas, epimastigotas e tripomastigotas de T. cruzi. Tais análises indicam uma maior detecção da proteína TcSCC1 na forma amastigotas de T. cruzi, apresentando variações no padrão da localização nuclear. Nas formas epimastigotas um sinal fraco foi detectado e nas formas tripomastigotas não houve sinalização. Estes resultados sugerem a presença da proteína TcSCC1 do complexo coesina principalmente no núcleo das formas amastigotas de T. cruzi. Os níveis de expressão dos genes para as quatro subunidades da coesina foram analisados por RT-PCR em tempo real nas três formas do T. cruzi e verificamos poucas diferenças entre estes níveis, o que sugere um controle pós-transcricional na expressão da SCC1 em T. cruzi. ______________________________________________________________________________ ABSTRACT
The segregation of sister chromatids to opposite poles of the cell during division is the most complex and, at the same time, the most important event during the life cycle of a eukaryotic cell. Both in mitosis and meiosis cohesion between sister chromatids is essential for the occurrence of the correct chromosomal segregation. The protein complex responsible for cohesion between chromatids is called Cohesin. The Cohesin complex is well known in yeast and mammals, consisting of two SMC (structural maintenance of chromosomes) proteins, SMC1 and SMC3, and two proteins SCC (sister chromatid cohesion) proteins, the SCC1 and SCC3 (SA1 and SA2 in mammalian cells). The Cohesin keeps sister chromatids together from S phase until the transition between metaphase and anaphase in cell cycle, when sister chromatids separate to the opposite poles of the cell. In trypanosomatids, there are few studies about this complex and the genome project revealed the presence of all Cohesin complex genes in Trypanosoma cruzi, Trypanosoma brucei and Leishmania major. In this work we proposed the analysis of the expression of the Cohesin subunits and its imunocytolocalization in T. cruzi cells. An antibody anti-TcSCC1 produced in rabbit, was used in western blots and immunofluorescence confocal microscopy analyses of amastigote, epimastigote and trypomastigote forms of T. cruzi. These analyses indicate that the TcSCC1 protein is detected mainly in the amastigote forms with distinct pattern of nucleus localization. Epimastigote form presented a weak signal for the anti-SCC1 antibody and trypomastigote form presented no signal. These results suggest that the SCC1 subunit of the Cohesin complex is present in T. cruzi and it is mainly evident in the nucleus of amastigote form of this parasite. The expression levels of each subunit of the Cohesin complex were analyzed by real time RT-PCR assays in the three forms of T. cruzi and it was found few differences between these levels, suggesting a post-transcriptional control in the SCC1 expression in T. cruzi.
ACETO, ZUMBO DANILO. « Politica di coesione fondi strutturali e criminalità organizzata ». Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2013. http://hdl.handle.net/2108/92707.
Texte intégralCOMI, Chiara. « La coesione semantica in coppie cliniche : una ricerca esplorativa ». Doctoral thesis, Università degli studi di Bergamo, 2017. http://hdl.handle.net/10446/77258.
Texte intégralDAMIANI, FILIPPO. « Innovazione, coesione sociale e disuguaglianze in Europa : un’analisi poset ». Doctoral thesis, Università degli studi di Modena e Reggio Emilia, 2022. http://hdl.handle.net/11380/1274340.
Texte intégralThis dissertation stems from a co-tutored doctoral project between the University of Modena and Reggio Emilia and the Pablo de Olavide University of Seville. The main objective consisted in the development of two topics related to innovation, social cohesion and inequalities in Europe in three different papers. The common thread consists in the methodology used: the partially ordered set (poset), a method based on the assumption that an object can be identified as "better" than another if and only if it has better results in all the indicators analysed in the comparison. We have chosen to use this methodology to propose an alternative analysis of the data (compared to the existing in the literature), based on rankings built on the simple arithmetic mean of the normalised indicators. In the first two papers we focused on the vast theme of regional innovation, analysing the performance at the regional level of 220 regions in the first paper, and of 60 regions (those of the four greatest countries of southern Europe, namely Greece, Italy, Portugal, and Spain) in the second paper. For both papers, we used data from the Regional Innovation Scoreboard 2019, through which we built a ranking, dividing the regions analysed into different performance levels. The creation of clusters of similar regions combined with poset analysis, allowed us to identify differences between the ranking presented in this thesis and the ranking proposed by the Regional Innovation Scoreboard. In particular, it was possible to identify the indicators that have the greatest impact in determining the results, and consequently the movements of the regions in the ranking, making it possible to propose targeted policies based also on the country or cluster of regions analysed. In the analyses conducted, one of the most impacting indicators is Individual design applications per billion GDP (in purchasing power standards). Regarding the leaders of the analysis, we found that the majority are regions housing the capital city of the country. The third paper addressed the issue of gender inequalities in the digital economy by using the data of the Women in Digital Scoreboard 2020 concerning the 27 countries of the European Union and the United Kingdom. Also in this case, a ranking of countries split into four performance levels was obtained. The impact analysis of the indicators revealed that the most meaningful are: % of people with above basic digital skills in information, communication, problem solving and software for content creation; Graduates in STEM subjects per 1000 individuals aged 20-29; Gender pay gap in unadjusted form, considering all employees working in firms with ten or more employees. In this case, the sensitivity analysis performed on the indicators, made it possible to identify strengths and weaknesses of the individual countries. At the same time, the findings helped us to propose areas of intervention aimed at improving the results in the most critical indicators in order to increase the position in the ranking. The results also highlighted important differences between the different European macro-regions; in particular, nations belonging to southern and eastern Europe are clearly behind to those belonging to the north and a large part of western Europe.
RAPETTI, ELISA. « Generazioni e reti sociali. Uno studio esplorativo sulla coesione sociale ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/28990.
Texte intégralMorroni, Marta <1993>. « Destination wedding tourism. Una rete d’impresa in coesione con il territorio ». Master's Degree Thesis, Università Ca' Foscari Venezia, 2020. http://hdl.handle.net/10579/18339.
Texte intégralShimada, Márcia Kiyoe. « Caracterização das proteínas coesina e condensina do protozoário Trypanosoma cruzi (Chagas, 1909) ». Universidade Estadual de Londrina. Centro de Ciências Biológicas. Programa de Pós-Graduação em Microbiologia, 2006. http://www.bibliotecadigital.uel.br/document/?code=vtls000161916.
Texte intégralThe cohesin and condensing protein belong to the family of structural maintenance ofthe chromosomes (SMC) proteins, highly conserved from yeast to humans. They playimportant roles in cell division since they are involved in the chromosome condensation andsister-chromatid cohesion. We have identified the orthologs of these proteins in the protozoanTrypanosoma cruzi Dm28c. This parasite presents peculiarity characteristic such as thechromosome condensation limited and the maintenance of the nuclear envelope integrityduring the cell division, which makes it a challenging model to study the function of theSMC. The genes encoding for two cohesins (SMC1 and Scc1) and two condensins (SMC4and Cap-D2) were characterized both by Southern and Northern blots and in silico analysis.The data show that TcSMC1, TcScc1, TcSMC4 and TcCap-D2 are single copy genes in thegenome of the T. cruzi Dm28c and all of them are transcribed into mRNAs. The alignment ofthe deduced amino acid sequences from the SMC genes of T. cruzi, T. brucei, L. major, X.laevis, C. elegans, H. sapiens, S. pombe and S. cerevisiae showed that the conserved motifs ofthe SMC proteins are present in all the organisms mentioned above, suggesting that thestructure of these proteins was conserved during the evolution, which is important to theirATPase function and DNA interactions. By immunofluorescence, the proteins are localized inthe nucleus. Furthermore, the Western blot analysis showed that SMCs are expressed in theepimastigote and trypomastigote form for SMC4 and Cap-D2 condensin. Whereas SMC1 andScc1 cohesin could be detected only in the epimastigote stage, suggesting that those proteinsare important for the replication and not for the differentiation of the parasite. It also raises aninteresting hypothesis that SMC proteins might participate of the functional regulation ofchromatin by modulating its spatial organization in the nucleus and consequently modulatingthe gene expression of the parasite.
Cunha, Ricardo Jorge Romano Teixeira. « Avaliação do transporte sedimentar coesivo e misto ». Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11453.
Texte intégralA dissertação apresentada pretende contribuir para o conhecimento do transporte dos sedimentos coesivos e mistos. A análise dos processos que envolvem o transporte sedimentar deste tipo de sedimentos é complexa e de difícil avaliação, pois estão associados inúmeros fatores que condicionam o seu comportamento. Um conhecimento mais aprofundado do seu transporte sedimentar, leva a que as questões inerentes aos estuários sejam antecipadas e possam assim ser tomadas as devidas precauções. A avaliação do comportamento dos sedimentos coesivos assentou em ensaios laboratoriais efetuados no canal de hidráulica do Departamento de Engenharia Civil da Universidade de Aveiro. Nestes ensaios fez-se variar o tipo de sedimentos (amostras naturais e tratadas laboratorialmente), as condições hidrodinâmicas e a duração do período de análise. Para cada ensaio foram avaliados os volumes erodidos da secção teste, tendo-se verificado que as amostras tratadas apresentam maiores volumes de erosão comparativamente às naturais. Quanto à duração do ensaio verificou-se que para ambos os tipos de amostras, o aumento do tempo do ensaio conduz a maiores volumes de erosão, sendo esse aumento superior no caso das amostras naturais. Para avaliar o impacto da composição granulométrica, foi adicionada areia às amostras recolhidas, tendo-se verificado que a presença de uma maior percentagem de areia conduz a maiores volumes de erosão.
The presented thesis intends to contribute to a better knowledge regarding cohesive and mixed sediment transport. The behavior of this type of sediment is complex and difficult to assess, given the fact that there are a several factors conditioning their behavior. A better knowledge of their transport allows anticipating inherent questions to estuaries and taking precautionary measures. The cohesive sediment behavior evaluation was based on laboratory tests performed in a hydraulic flume at the Civil Engineering Department of the University of Aveiro. These tests were conducted modifying the type of sediment (natural and laboratory treated samples), hydrodynamic conditions and the test duration. The eroded volume of the test section for each test was determined, and has been verified that treated samples present a higher erosion volume when compared to natural samples. Concerning the duration of the test, it has been verified that, for both samples, the period increase leads to higher eroded volumes, particularly in the case of natural samples. Regarding the evaluation of the impact of granulometric composition, by the addition of sand to the natural samples, it was verified that the increase of the sand percentage leads to an increase in erosion volume.
Muccigrosso, Teo <1977>. « La valutazione degli effetti delle politiche di coesione dell'Unione europea sulla crescita regionale ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1997/1/MUCCIGROSSO_Teo_tesi.pdf.
Texte intégralMuccigrosso, Teo <1977>. « La valutazione degli effetti delle politiche di coesione dell'Unione europea sulla crescita regionale ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1997/.
Texte intégralLandolina, Damiano <1992>. « La Politica di coesione europea : Il Mezzogiorno d'Italia nella Programmazione finanziaria 2007-2013 ». Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/15110.
Texte intégralDi, Fiore Silvia. « La dimensione discorsiva della Politica di Coesione. Confronto fra Content Analysis e Topic Modeling ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/17284/.
Texte intégralMASCENA, Alberto. « Coesione semantica e unioni miste. Un'indagine esplorativa con il modello delle polarità semantiche familiari ». Doctoral thesis, Università degli studi di Bergamo, 2017. http://hdl.handle.net/10446/77273.
Texte intégralACETO, DANILO. « Politica di coesione fondi strutturali e criminalità organizzata Cohesion policy structural funds and organized crime ». Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2013. http://hdl.handle.net/2108/111505.
Texte intégralAmbrosio, Miriam Carla Bonicontro. « Secagem de particulado coesivo em secador de leito fluidizado agitado ». [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267552.
Texte intégralDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: O presente trabalho experimental foi realizado com o intuito de verificar a viabilidade da utilização do leito fluidizado agitado em processo de secagem de um ácido orgânico particulado fino, com características coesivas quando úmido. Numa primeira etapa foi feito um estudo da influência da agitação na fluidodinâmica do leito fluidizado utilizando partículas de celulose micro - cristalina isenta de umidade visando avaliar a fluidodinâmica da fluidização sob agitação. Observou-se que a curva de fluidização não passava pelo pico de queda de pressão máxima. Numa segunda etapa utilizou-se a metodologia de planejamento experimental para estudar a influência das variáveis operacionais como altura de leito fixo, da temperatura do gás de secagem e a umidade inicial do material sobre a taxa de secagem. O planejamento 23 usado para o desenvolvimento das corridas experimentais mostrou que as variáveis independentes umidade inicial e altura do leito fixo são os fatores que afetam a taxa de secagem de maneira significativa. Numa terceira etapa foram traçadas curvas características de secagem, X/Xo versus t, que apresentaram o período de taxa de secagem constante bem definido durante todo o processo de secagem, para os dois métodos de análise de umidade utilizados, método da estufa e de Karl-Fischer. Na etapa final do trabalho, foi feita a caracterização física dos cristais secos no leito fluidizado agitado, e foi observado que a umidade final obtida estava dentro dos padrões comerciais aceitos, os cristais tinham a coloração branca e o formato esperado de agulhas, bem como baixa concentração de finos
Abstract: The experimental work and study, now being considered, were carried out for the purpose of verifying the feasibility of usefulness of an agitated fluidized bed in the drying process of a particulate organic acid. Firstly, it was conducted a series of experiments in order to understand the influence of agitation on the hydrodynamics of fluidized beds, utilizing micro-crystalline cellulose particles. It could observed that the pressure drop curves skipped the maximum pressure drop brink observed in conventional fluidization curves. Following, the methodology of experimental design was used to study the influence of the process variables, namely, bed height, drying gas temperature and particle initial moisture content, on the drying rate of the particulate material. The 23 design utilized for the planning of the experimental runs, showed up that bed height and particle initial moisture content were two factors that mostly affected the drying rate. As for the drying kinetics, the whole drying process took place at a constant rate, for each experiment carried out. This result was obtained by means of the oven method and corroborated by the Karl - Fischer titration method. In the last part of this work, it was made a physical characterization of the dried crystals in the agitated fluidized bed and it was found that the characteristics of moisture content and particle size were within the commercial standards accepted for this kind of material
Mestrado
Engenharia de Processos
Mestre em Engenharia Química
Fabbi, Irene. « Effetti del creep dei terreni coesivi sulla stabilità delle torri ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2635/.
Texte intégralSilva, Fabiana Brandão Alves. « Análise da expressão gênica da proteína homóloga à Scc1/Rad21 do complexo Coesina em Trypanosoma cruzi ». reponame:Repositório Institucional da UnB, 2012. http://repositorio.unb.br/handle/10482/10953.
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O complexo Coesina tem a função essencial de assegurar a correta segregação das cromátides irmãs após replicação do DNA. A Coesina atua tanto na mitose como na meiose e é mais bem descrita em leveduras e mamíferos. O complexo se forma pela interação das subunidades proteicas conhecidas como SMC (proteínas de manutenção estrutural dos cromossomos), SMC1 e SMC3, e duas proteínas SCC (proteínas de coesão das cromátides irmãs), a SCC1 (também conhecida como Mcd1 ou Rad21) e SCC3 (SA1 e SA2 em células de mamíferos). Existem poucos estudos sobre a Coesina e sua função em tripanossomatídeos, sendo que foi verificada a presença dos genes para todas as subunidades da Coesina em Trypanosoma cruzi, Trypanosoma brucei e a Leishmania major. Em trabalhos recentes do nosso grupo, foi observado que a subunidade SCC1 do complexo Coesina em T. cruzi está presente nas formas amastigotas com localização nuclear, em menor quantidade em epimastigotas distribuída por toda a célula e ausente em tripomastigotas. Desse modo, essa diferença da presença da proteína TcSCC1 nas diferentes formas do parasita nos levou a estudar nesse trabalho a expressão gênica dessa proteína de T. cruzi e sua regulação. Inicialmente, foi realizada uma quantificação relativa do mRNA da proteína SCC1 nas diferentes formas do T. cruzi por RT-PCR em tempo real. As formas amastigotas e tripomastigotas apresentaram uma quantidade relativa semelhante entre si e equivalente à metade da quantidade das formas epimastigotas, o que diverge do observado para a presença da proteína. Assim, é possível que haja um mecanismo regulatório provavelmente pós-transcricional, já que é descrito que esse tipo de regulação é peça chave na modulação da expressão gênica em T. cruzi. Nos experimentos onde foi inibido a transcrição e a transcrição juntamente com a tradução nas formas epimastigotas e amastigotas, observamos uma estabilidade do mRNA da TcSCC1 mais longa em amastigotas e pouco afetada com a inibição da tradução. Essa observação pode explicar a causa da maior abundância da proteína nas formas amastigotas. Embora em epimastigotas o mRNA também seja relativamente estável, a quantidade relativa decresce mais acentuadamente, sugerindo uma meia vida mais curta em epimastigotas. É provável que a regulação pós-transcricional desse mRNA possa estar modulando a expressão do gene TcSCC1 entre as formas do T. cruzi e essa não é dependente da tradução. _________________________________________________________________________________ ABSTRACT
The cohesin complex has the essential function of ensuring the correct segregation of sister chromatids after DNA replication. The cohesin acts both in mitosis as in meiosis and is best described in yeast and mammals. The complex is formed by the interaction of protein subunits known as SMC (structural maintenance of chromosomes), SMC1 and SMC3, and two proteins SCC (cohesion of sister chromatids), the SCC1 (also known as Mcd1 or Rad21) and SCC3 (SA1 and SA2 in mammalian cells). There are few studies of the cohesin and its function in trypanosomatids, and it was detected the presence of genes for all subunits of cohesin in Trypanosoma cruzi, Trypanosoma brucei and Leishmania major. In recent work from our group, we observed that the SCC1 subunit of cohesin complex in T. cruzi amastigotes is present with nuclear localization, in epimastigotes with a lesser amount distributed throughout the cell and absent in trypomastigotes. Thus, this difference of the presence of TcSCC1 protein in the different forms of the parasite led us to study in this work the gene expression of this T. cruzi protein and its regulation. Initially, we performed a relative quantification of TcSCC1 mRNA in the different forms of T. cruzi by real time RT-PCR. The amastigotes and trypomastigotes forms presented a relative similar amount among themselves and as equivalent to half the amount of the epimastigote forms, which differs of that observed for presence of the protein. Thus, there may be a possible post-transcriptional regulatory mechanism, since it is reported that this type of regulation is a key part in the modulation of T. cruzi gene expression. In experiments where transcription was inhibited and transcription along with translation in epimastigotes and amastigotes, we observed longer stability of TcSCC1 mRNA in amastigotes and is not affected by the inhibition of the translation. This observation may explain why the protein is more abundant in amastigotes. Although in epimastigotes the mRNA is also relatively stable, the relative amount decreases more markedly, suggesting shorter half life in epimastigotes. It is likely that post-transcriptional regulation of this mRNA may be modulating the TcSCC1gene expression between the forms of T. cruzi and that is not dependent on translation.
Henry, Caroline. « L'unité à coesite du massif Dora-Maira (Alpes occidentales, Italie) dans son cadre pétrologique et structural ». Paris 6, 1990. http://www.theses.fr/1990PA066169.
Texte intégralMarrone, Vincenzo <1975>. « L’abitare come relazione sociale : il significato della casa e i processi di coesione sociale di vicinato ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5438/1/marrone_vincenzo_tesi.pdf.
Texte intégralThe current social changes enhance the uncertainty, displacement and individualism perception, but at the same time, some practices contrast with the dominant trend. These practices are aimed to create local social ties. For instance, the urban-architectural planning is embodying the growing need for community, developing housing solutions aimed to increase informal neighbors exchanges. So it relies on the terms of social capital, neighborhood attachment, place identity, participation. Home, the symbol of stability and safety, but also, privacy and familiar privatism, increasingly becomes the object of sociological studies, social question and policy action. It is increasingly understood as a node within widest networks of household relationships. In which extent home and neighbourhood community affect to the family well-being and sociability? In which extent the urban-architectural spaces impact on social cohesion levels? What is the role of inhabitants in developing sociability and integration? Starting from these research questions, we explore the social and cultural dynamics of inhabiting, using a case study in two similar planned neighbourhoods. The research findings highlight that the meaning of home is not unique but it changes in function of the family life cycle and economic status. So, the meanings of the home are linked with the neighborhood activities’ participation. The findings show that the physic built space creates important chances for informal exchanges, family and children well-being but, also that, the social context is the determinant of the social benefits. Comparing the neighborhoods, the one in which a inhabitants association is present, the number of neighbor relations and the physic distances between them increase, as well as the quality of relations between neighbors improves. Furthermore, it seems that the reciprocity is the principal mean about the constitution of the internal community cohesion and it also creates an openness and trust attitude that goes beyond the neighbourhood boundaries.
Marrone, Vincenzo <1975>. « L’abitare come relazione sociale : il significato della casa e i processi di coesione sociale di vicinato ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5438/.
Texte intégralThe current social changes enhance the uncertainty, displacement and individualism perception, but at the same time, some practices contrast with the dominant trend. These practices are aimed to create local social ties. For instance, the urban-architectural planning is embodying the growing need for community, developing housing solutions aimed to increase informal neighbors exchanges. So it relies on the terms of social capital, neighborhood attachment, place identity, participation. Home, the symbol of stability and safety, but also, privacy and familiar privatism, increasingly becomes the object of sociological studies, social question and policy action. It is increasingly understood as a node within widest networks of household relationships. In which extent home and neighbourhood community affect to the family well-being and sociability? In which extent the urban-architectural spaces impact on social cohesion levels? What is the role of inhabitants in developing sociability and integration? Starting from these research questions, we explore the social and cultural dynamics of inhabiting, using a case study in two similar planned neighbourhoods. The research findings highlight that the meaning of home is not unique but it changes in function of the family life cycle and economic status. So, the meanings of the home are linked with the neighborhood activities’ participation. The findings show that the physic built space creates important chances for informal exchanges, family and children well-being but, also that, the social context is the determinant of the social benefits. Comparing the neighborhoods, the one in which a inhabitants association is present, the number of neighbor relations and the physic distances between them increase, as well as the quality of relations between neighbors improves. Furthermore, it seems that the reciprocity is the principal mean about the constitution of the internal community cohesion and it also creates an openness and trust attitude that goes beyond the neighbourhood boundaries.
Neiva, Natalia Antunes. « Efeito da clorexidina e flúor na resistência coesiva da estrutura dental irradiada e não irradiada ». Universidade Federal de Uberlândia, 2010. https://repositorio.ufu.br/handle/123456789/16914.
Texte intégralRadiation therapy significantly reduces the resistance of the tooth structure and the damage is potentially higher in the organic matrix. The use of products that promote the stabilization of collagen and / or agents to intensify the cross-links may provide less damage to the resistance of teeth irradiated. This study aimed analyze the effect of the use of chlorhexidine and sodium fluoride in the cohesive strength of the tooth structure during radiotherapy in head and neck believing that these products may influence the mechanical properties of enamel and dentin. Were collected 60 teeth divided into 2 groups, irradiated and non-irradiated, subdivided into 2 mouthwash protocols used 3 times a day: 0.12% chlorhexidine and 0.05% sodium fluoride and a control group. The specimens were evaluated by microtensile testing. The Tukey test (P <0.05) revealed that the presence of irradiation reduces the UTS of enamel, crown and root dentin regardless of the orientation of the prisms and tubules. The simulating of rinsing with chlorhexidine 0.12% recovered the resistance of crown dentin irradiated transversal to tubule orientation (GIP= 45,1 7,8 Ab), (GIT= 57,6 12,5 Aa), (GNIP= 76,2 12,5 Ab), (89,4 16,7 Aa) and the simulating of rinsing with sodium fluoride at 0.05% recovered the resistance of enamel irradiated making it similar to the non-irradiated enamel (GIP= 38,5 ± 4,9Aa), (GIT= 15,9 ± 2,7Aa), (GNIP= 43,2 ± 13,7Aa), (GNIT= 18,0 ± 2,0Aa). Therefore, the use of those substances for radiation treatment becomes essential to reduce the side effects and improve the quality of life of cancer patients in the head and neck.
A radioterapia reduz significativamente a resistência da estrutura dental e os danos são potencialmente maiores sob a matriz orgânica. A utilização de produtos que promovam a estabilização do colágeno e/ou agentes que intensifiquem as ligações cruzadas podem prover menores danos à resistência da estrutura dental irradiada. Este estudo objetivou analisar o efeito do uso da clorexidina e fluoreto de sódio na resistência coesiva da estrutura dental durante o processo de radioterapia na região de cabeça e pescoço acreditando que estes produtos podem influenciar as propriedades mecânicas do esmalte e dentina. Foram coletados 60 dentes terceiros molares humanos que foram divididos em 2 grupos, irradiado (GI) e não irradiado (GNI), subdivididos em 3 sub-grupos de acordo com o protocolo de tratamento tópico recebido: Bochecho com clorexidina a 0,12%, fluoreto de sódio a 0,05% e grupo controle. A resistência à microtração foi analisada. O teste de Tukey (P <0.05) revelou que a radiação reduz a resistência coesiva do esmalte, dentina coronária e dentina radicular independente da orientação dos prismas e túbulos (paralela (P) e transversal (T). A simulação do bochecho com clorexidina a 0,12% recuperou a resistência da dentina coronária irradiada na orientação transversal (GIP= 45,1 7,8 Ab), (GIT= 57,6 12,5 Aa), (GNIP= 76,2 12,5 Ab), (89,4 16,7 Aa) e a simulação do bochecho com fluoreto de sódio a 0,05% recuperou a resistência do esmalte irradiado tornando-o semelhante ao esmalte não irradiado (GIP= 38,5 ± 4,9Aa), (GIT= 15,9 ± 2,7Aa), (GNIP= 43,2 ± 13,7Aa), (GNIT= 18,0 ± 2,0Aa). Portanto, o uso dessas substâncias durante o tratamento radioterápico torna-se fundamental para reduzir os efeitos colaterais e melhorar a qualidade de vida dos pacientes com câncer na região de cabeça e pescoço.
Mestre em Odontologia
Brischitti, Pierpaolo. « Topic Modeling nelle scienze sociali : Analisi automatica del testo applicata al dibattito sulle politiche europee di coesione ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Trouver le texte intégralČernok, Ana [Verfasser], et Leonid [Akademischer Betreuer] Dubrovinsky. « Diversity of compressional mechanisms among SiO2 polymorphs : case of coesite and cristobalite / Ana Cernok. Betreuer : Leonid Dubrovinsky ». Bayreuth : Universität Bayreuth, 2015. http://d-nb.info/1081718102/34.
Texte intégralSouza, Agnelo Rodrigues de. « Divisão celular do Trypanosoma cruzi : o papel da subunidade TcSCC1 do complexo coesina e das proteínas centrinas ». reponame:Repositório Institucional da UnB, 2016. http://repositorio.unb.br/handle/10482/21353.
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Durante o processo de divisão celular os tripanossomatídeos e alguns microrganismos do reino Fungi mantém o núcleo intacto em um processo denominado de mitose fechada. Além disso, os tripanossomatídeos não apresentam condensação da cromatina e ocorre um alongamento do núcleo para acomodar os cromossomos já replicados. Em leveduras e metazoários, a manutenção das cromátides irmãs juntas durante a divisão celular até a sua separação na transição metáfase e anáfase é realizada pelo complexo coesina. Análise dos genomas de tripanossomatídeos mostrou que genes do complexo coesina e de proteínas centrinas estão presentes e são conservados. Para investigar a função da subunidade TcSCC1 do complexo coesina e das cinco proteínas centrinas preditas em T. cruzi, o agente etiológico da doença de Chagas, foram feitas clonagens dos genes TcSCC1 e TcCEN1 a 5. Para a análise de citolocalização dessas proteínas no parasita, os genes TcSCC1, TcCEN2, 4 e 5 foram subclonados no vetor de expressão transiente pRTEGFP que contém o promotor ribossomal, a região 5’UTR do gene para a amastina, o gene para a proteína fluorescente verde (EGFP) e a região 3’UTR do gene TCR27. A subclonagem foi realizada de modo que as proteínas de estudo foram expressas como fusão no N-terminal da EGFP. Esses plasmídeos foram utilizados em transfecção transiente e a expressão da EGFP com e sem as fusões proteicas foram visualizadas por microscopia de fluorescência. As centrinas 2, 4 e 5 e a subunidade TcSCC1 da coesina fusionadas com EGFP apresentaram uma localização predominantemente nuclear, embora não exclusivo, quando comparado com a EGFP sem fusão. Para verificar se as proteínas estudadas são expressas em T. cruzi foram realizadas análises de PCR quantitativa nas suas três formas de vida: amastigotas, epimastigotas e tripomastigotas. Verificamos que todos os genes são expressos na forma de mRNA. As centrinas 2 e 5 apresentaram a maior expressão relativa nas três formas enquanto que as centrinas 1 e 3 apresentaram expressão equivalente à GAPDH em amastigotas e epimastigotas, mas em tripomastigotas uma expressão maior. A centrina 4 apresentou uma expressão relativa muito menor que a GAPDH e às outras centrinas nas três formas do parasita. Deste modo, concluímos que as cinco centrinas e a subunidade SCC1 são expressas em T. cruzi com uma possível localização nuclear. ________________________________________________________________________________________________ ABSTRACT
During cell division the trypanosomatids and some fungi microorganisms keeps the nucleus intact in a so-called closed mitosis. Furthermore, the trypanosomes do not show chromatin condensation and it occurs nucleus elongation to accommodate the replicated chromosomes. In yeast and metazoan, maintenance of sister chromatids together during cell division until their separation in metaphase and anaphase transition is performed by cohesin complex. Analysis of trypanosomatid genomes showed that genes for the cohesin complex and for centrin proteins are present and conserved. To investigate the function of TcSCC1 subunit of cohesin complex and the five predicted centrin proteins in T. cruzi, the causative agent of Chagas disease, cloning of the TcSCC1 gene and all five TcCEN genes was performed. For cytolocalization analysis of these proteins in the parasite, TcSCC1 and TcCEN2, 4 and 5 genes were subcloned into the transient expression vector pRTEGFP that contains the ribosomal promoter, the 5'UTR region of the amastin gene, the gene for green fluorescent protein (EGFP) and the 3'UTR region of the TCR27 gene. Subcloning was performed so that the proteins were expressed as fusion proteins at the N-terminus of EGFP. These plasmids were used in transient transfection and expression of EGFP with and without the protein fusions were visualized by fluorescence microscopy. The centrins 2, 4 and 5 and TcSCC1 cohesin subunit fused to EGFP showed a predominantly nuclear localization, although not unique, when compared to EGFP without fusion. To verify that the studied proteins are expressed in T. cruzi quantitative PCR analysis was performed in its three forms of life: amastigotes, epimastigotes and trypomastigotes. We found that all genes are expressed as mRNA. The centrins 2 and 5 had the highest relative expression in three forms while centrins 1 and 3 had equivalent expression to GAPDH in amastigotes and epimastigotes, but higher expression in trypomastigotes. The centrin 4 showed a much smaller relative expression to GAPDH and the other centrins in the three forms of the parasite. Thus, we conclude that the five centrins and the SCC1 subunit are expressed in T. cruzi with a possible nuclear localization.
Ingrin, Jannick. « Microscopie électronique en transmission de géomatériaux : volcanisme : produits pyroclastiques des Antilles ; métamorphisme : coesite dans un quartzite alpin ». Paris 7, 1985. http://www.theses.fr/1985PA07F066.
Texte intégralRizza, Debora <1992>. « La politica di coesione post 2020 nella prospettiva della governance multilivello : il caso della Regione del Veneto ». Master's Degree Thesis, Università Ca' Foscari Venezia, 2020. http://hdl.handle.net/10579/16394.
Texte intégralFernandes, Ricardo Albuquerque. « Acoplamento med-mef associado a modelos da mecânica da fratura coesiva ». Universidade Federal de Alagoas, 2012. http://www.repositorio.ufal.br/handle/riufal/3506.
Texte intégralFUNDEPES - Fundação Universitária de Desenvolvimento de extensão e Pesquisa
PRH-ANP - Programa de Recursos Humanos da Agência Nacional do Petróleo
Este trabalho propõe a modelagem computacional do comportamento mecânico bidimensional de meios com abordagens contínua, relacionada ao Método dos Elementos Finitos (MEF) associado a modelos da Mecânica da Fratura Coesiva (MFC) e discreta, através do Método dos Elementos Discretos (MED). O MEF consiste em uma ferramenta numérica bastante utilizada na determinação de soluções aproximadas para problemas da Mecânica do Contínuo, envolvendo fenômenos com não linearidades físicas e geométricas associadas e com comportamento quase-estático ou dinâmico, possuindo aplicações práticas já consagradas em diversas áreas do campo científico e industrial. Por outro lado, o MED tem desenvolvimento mais recente e vem sendo cada vez mais utilizado no tratamento de problemas de natureza discreta envolvendo fenômenos de contato, impacto, fragmentação e fluxo de sistemas particulados. Com foco na análise de problemas que envolvem interações entre tais naturezas, implementa-se uma estratégia de acoplamento MEF-MED para solução do problema em subregiões, onde o MEF é utilizado na modelagem de processos de nucleação e propagação de fraturas em meios contínuos e o MED é empregado na modelagem de meios granulares por natureza, ou assim concebidos, em comportamento transiente. A possibilidade de abertura e propagação de fraturas é considerada através da utilização de modelos da MFC, incorporados intrinsecamente na formulação do MEF através de interfaces inseridas nas arestas internas da malha de elementos finitos. Exemplos ilustrativos são apresentados e discutidos visando-se validar a formulação e a implementação propostas.
Barcelos, Amauri Antunes. « Geração de sulcos em meio coesivo e caracterização hidrossedimentométrica de sua evolução ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2005. http://hdl.handle.net/10183/7652.
Texte intégralWithin the field of erosion research, a consensus has been forming during the past few decades that it is important to understand the basic processes responsible for the phenomenon. One of the strategies toward a better understanding of the stages of erosion is to separate the rill (concentrated flow) and inter-rill phases. With this in mind, was constructed in the Erosive and Depositional Processes Laboratory (LaPED) of the Hydraulic Research Institute of the Federal University of Rio Grande do Sul (IPH/UFRGS) an experimental flume with which to study the process of incision and rill development. This structure enables flow rate to be controlled via an electromagnetic sensor, and the grade to be changed using a hydraulic system associated with a digital level. The soil placed in the flume was a typical dystrophic red oxisol, the working slopes were 3.0, 6.0 and 9.0% and the sequence of flow rates applied were 10.0, 18.5, 25.5, 38.5 and 51.0 L.min-1. The flume proved easy to operate and was an efficient way to advance in the understanding of disaggregation and solid particle transport processes via surface runoff, as well as enabling the creation of rills on the soil surface. Runoff, initially diffuse, became concentrated once the surface flow rate reached 0.26m.s-1, the height of the sheet of water reached 0.0102m, shear velocity exceeded 0.059m.s-1, shear stress reached 3.5Pa, and stream power reached approximately 0.22N.s- 1. The incision process began when the flume was at low slope and with sub-critical and transitional runoff regimes. Shear velocity, at the moment of incision, was practically double that encountered in the literature for silty and sandy soils. Nonetheless, for the three slopes used, the rill phase occurred only with turbulent runoff. Shear stress was the parameter which best described the evolution of soil loss, while stream power was the most efficient hydraulic parameter for separating the different evolutionary phases of the rills. With diffuse runoff (without rills), the stream power oscillated between 0.057 and 0.198N.s-1. Rill progression began with a transitionary period (incision and deepening phases) in which the stream power varied between 0.220 and 0.278N.s-1, and was immediately followed by the defined rill phase, with stream power between 0.314 and 0.544N.s-1. During the concentrated runoff phase, regressive erosion processes played a key role in increasing both the size and weight of the particles being transported by the surface runoff, so that bed load transport predominated over suspended sediment transport. The sediment loads generated with soils of different textural classes were separated in different groups depending on their unit stream power.
Bosch, Dante Rene. « Interpretação do ensaio pressiométrico em solos coesivo-friccionais através de métodos analíticos ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1996. http://hdl.handle.net/10183/35971.
Texte intégralA methodology has been developed in this research programme to predict soil properties from cemented soils on the basis of Ménard pressuremeter test results. Analytical solutions based on Cavity Expansion Theory are used to derive realistic soil parameters from elasto-perfectly plastic formulations. Two methods have been used in the analysis. Both were implemented on spreadsheets available for commercial application on micro-computers. All calculations are carried out in the computer, aliowing a visual comparison between experimental and theoretical results. The parameters obtained on a perfect curve fitting analysis will correspond to those that describe soil behaviour satisfactorily. Validation of proposed methodology is based on a field programme designed to test gravite weathered soils from the Porto Alegre area. Parameters obtained from the pressuremeter cavity expansion analysis have been compared to parameters derived from a conventional pressuremeter interpretation, as well as from the laboratory test results. The comparison shows a good agreement between measured and predicted data, which suggest that the pressuremeter is a useful tool to assess soil properties from cohesive-frictional materiais.
Burchini, Martina. « Analisi contrastiva degli elementi di struttura e coesione testuale di sentenze penali italiane, austriache e tedesche in un'ottica traduttiva ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8153/.
Texte intégralPalazon, Milena Traversa. « Avaliação da influência da técnica incremental na força coesiva de diferentes resinas compostas ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/23/23134/tde-17122013-154725/.
Texte intégralThe aim of this study was to evaluate the influence of incremental technique on the cohesive strength of different dental resin composites. A total of 120 conical specimens of different resin composites, Filtek P90 and Filtek Z350 XT, both in color A3, were made in a bipartite teflon device with the following dimensions: 4 mm base diameter of 2mm and 8mm in height. The specimens were assigned into 12 groups (n = 10), 6 groups without the use of adhesive and 6 groups with the use of adhesive. The cavity was filled with a metal spatula in oblique or horizontal increments of 2mm thick or inserted at once in one portion 4mm thick and each increment was light-cured for 20 seconds following manufactures instructions. The specimens were subjected to microtensile tests to evaluate the cohesive strength of the resin composite and the influence of incremental technique used. Data were submitted to ANOVA and Tukey\'s HSD test (p<0,05%).Can be concluded that the incremental technique using increments oblique negatively influence the cohesive strength. The resin Filtek Z350XT has greater cohesive resistance when compared to Filtek P90. The use of adhesive negatively influence the cohesive resistance
Averbeck, José Henrique Costa. « O cone elétrico e sua aplicação no estudo de fundações em solos coesivo-friccionais ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1996. http://hdl.handle.net/10183/33690.
Texte intégralAn experimental programe making use of an electrical cone rig was carried out in the Federal University of Rio Grande do Sul (UFRGS) geotechnical testing site in the city of Cachoeirinha, province of Rio Grande do Sul, Brazil. The electrical cone test provide a continuous measurement of cone tip resistance and local side friction. The present study is related to the interpretation of electrical CPT data in cohesive-frictional soils. Interpretation of CPT records were used to investigate some aspects of soil properties and foundation behaviour. The electrical CPT proved to be an efficient tool to establish soil stratigraphy, as well as to determine Pedologic horizons. However, soil classification based on cone tip resistance (qc) and friction ratio (FR), used in sedimentary soils (Schmertmann, 1978; Searle, 1979; Douglas & Olsen, 1981 e Robertson & Campanella, 1983), proved to be inappropriated when applied to cohesive-frictional materiais. Determination of strength properties in cohesive-frictional soils through penetration tests cannot make use of correlations for sedimentary soils, once the soil shear strength is expressed in terms of two variables - internai frictional angle and cohesive intercept (c). Among analysed bearing capacity theories, only those proposed by Durgunoglu & Mitchell (1973) and Janbu & Senneset (1974) have demonstrated to be usefull on predicting shear strength parameters since the analytically predicted shear strength parameters is the same order of magnitude as the parameters obtained through direct shear tests. In parallel, semi-empirical correlations between cone tip resistance (qc) and Young's modulus were established. This study have also evaluated the applicability of current design methods for predicting bearing capacity of shallow foundations and piles on cohesive-frictional materiais. Pile and plate loading tests carried out in the experimental site were interpreted. The results of this analysis indicate that Aoki & Velloso method (1975) was the most accurate in the prediction of failure load while other methods (Van der Veen & Boresma, 1957; Te Kamp, 1977; Scmertmann, 1978; Philipponat, 1980 e Bustamante & Gianeselli, 1982) superestimate the ultimate load. Allowable bearing stresses of shallow foundation were estimated through obtainance of parameter M, defined as the ratio of qc and adm. Values of qc/adm range between 5,9 and 19,0; considerable scatter is observed which indicates the difficulty of applying this methodology in geotechnical design.
Orlando, Patrícia Del Gaudio. « Avaliação experimental da interação solo coesivo-fita polimérica sob condições de teor de umidade variáveis ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3145/tde-10112015-113843/.
Texte intégralCurrent specifications for reinforced soil structures generally require the use of granular backfill due to their high strength, well drainage capacity and low volume change potential. However, in cases where granular fills are not easily and readily available, poorly draining soils should be used to enable the implementation of a mechanically stabilized earth wall (MSEW). In Brazil, the fine-grained residual soils that cover large areas of its territory frequently present high shear strengths and low compressibility. However, the use of cohesive soils can cause unwanted effects in structure stability due to the water content variations of the backfill soil, and the potential development of pore-water pressures or loss of strength. On the other hand, matric suctions may increase the soil-geosynthetic interface shear strength. In this context, this study presents the experimental results and discusses the effects of seasonal climatic variations (wetting and drying) on shear strength of soil-geosynthetic straps interfaces under unsaturated conditions. For the laboratory investigation, a compacted residual soil of gneiss composed of 80% silty sand passed through a 0.075mm sieve, sourced from São Paulo city, and a high-tenacity polyester strap were used. Direct shear and pullout tests were conducted with three different net normal stresses and levels of matric suction, besides the inundated condition. Triaxial tests under saturated (CU) and unsaturated (CW) conditions with suction measurement using a high capacity tensiometer were performed in order to evaluate the shear strength parameters of the unsaturated soil, the interface efficiency of the soil-geosynthetic strap and the pore water pressure variations during shear. The results indicate that the cohesive soil used in this study has excellent shear strength parameters, a high capacity to maintain negative pore water pressures and presents an efficient interaction with the geosynthetics straps, which would allow the implementation of a stable MSEW for failure by pullout. Furthermore they reveal that the peak shear strength of the soil-geosynthetic strap interface increases nonlinearly with the soil suction, while the apparent friction factor (f*) decreases with the increase in molding moisture contents. On the other hand, the effect of suction on the post-peak shear strength of the interface was negligible.
Pereira, Vinícius Rocha Gomes. « Influência da pressão da água intersticial na resistência ao arrancamento de geogrelha em solo coesivo ». Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-06122011-110206/.
Texte intégralThe behavior of soil reinforcement structure depends on backfill soil and reinforcement interaction. The use of cohesive soils can cause negatives effects in structure stability. High quantities of fine particles in composition of soils can induce the pore water pressure development due to draining capacity reduction. Therefore, a negative effect of positive pore water pressure development is the reduction of reinforcement pullout forces embedded in resistant zone of soil reinforcement backfill. For designers, the better determinations of geogrids pullout forces are by pullout tests. This paper presented and describes the evaluation of small box pullout tests results conducted in lab. Low plasticity sand clayed was used in tests, which is composed by 35% of clay and silt particles. The reinforcement tested was a high strength uniaxial geogrid, with resistance of 110 kN/m. The tests are conducted with three different level normal stresses (25, 50 and 100 kPa), and samples compacted with 12,6%, 14,6% e 16,6% to moisture contents of Proctor tests. Pullout tests results showed the influence of moisture conditions in the geogrid pullout resistance. It was found that the highest matritial suction values resulted in the highest ultimate pullout resistance. Positive pore water pressure was obtained in three pullout tests though it did not influence in pullout strength results.
Valle, Carmen Lúcia Bueno. « O entrelaçar coesivo e a variação lingüística : um percurso didático-metodológico à luz da linguística textual ». Universidade Presbiteriana Mackenzie, 2009. http://tede.mackenzie.br/jspui/handle/tede/2782.
Texte intégralBased on the theoretical presuppositions of Textual Linguistics and grounded on postulates of the varied Socio-Linguistics, this research wishes to cause a reflection on the possibility of approximation between theory and practice, from verifying the results obtained from texts written by first-year high school students, diastratic linguistic variation users, by means of teaching strategies on text study, in its macro and micro structures. The purpose of this paper is to show that one of the possible ways leading to an effective practice of the Portuguese language teaching, especially in a context of linguistic variation, like the one presented by this alumni group, may be constructed by the teaching of Textual Linguistics, with the aim of making students become textually competent. Through the study of linguistic theories, the analysis was carried through students textual productions in two distinct periods: from the results of the application tests for the selection of applicants and a textual production done by the end of the year with high school students. In both occasions, the writing proposed to students was the same, the creation of a letter to a school newspaper. The comparative analysis between initial and final texts demonstrates a considerable progress in the linguistic competence and register, composed by the accuracy of correct spelling, the use of a wide variety of lexis, and mainly in the cohesion of the produced texts, which was the focus of this research, providing a valuable contribution to the meaning of the text, the coherence. The presentation of a standard pattern of writing was focused, and also a variant one to be used in certain situations, regarding the non-standard writing brought by students as an identity element to their socio-cultural universe. It was concluded that the students proper register and linguistic progress, mainly textual related progress, are possible by means of translating the Textual Linguistics into the practice of Portuguese Language Teaching.
Fundamentada nos pressupostos teóricos da Linguística Textual e respaldada pelas postulações da Sociolinguística variacionista, esta pesquisa busca suscitar uma reflexão sobre a possibilidade de aproximação entre teoria e prática, a partir da verificação dos resultados obtidos nos textos dos alunos de 1º ano de Ensino Médio, usuários de variação linguística de ordem diastrática, por meio de estratégias de ensino pautadas no estudo do texto, em suas macro e micro estruturas. Este trabalho pretende mostrar que um dos caminhos possíveis para a prática efetiva do ensino de Língua Portuguesa, em especial, em um contexto de variação linguística, como o que se apresentava por esse grupo discente, pode ser construído a partir dos ensinamentos da Linguística Textual, com o escopo de tornar os alunos competentes textualmente. A partir do estudo das teorias linguísticas, foi realizada a análise das produções textuais dos alunos em dois momentos distintos: na prova de seleção para ingresso no projeto e uma produção textual feita no final do ano letivo do 1º ano do Ensino Médio. Para as duas situações, utilizou-se a mesma proposta de redação que sugeria a elaboração de uma carta aberta a ser veiculada em um suposto jornal escolar. A análise comparativa entre textos iniciais e textos finais demonstra considerável avanço à competência linguística e apropriação da norma culta, observáveis na grafia correta das palavras, na ampliação do léxico e, principalmente, no entrelaçar coesivo dos textos produzidos foco desta pesquisa , contribuindo enormemente à construção do sentido do texto, a coerência. Priorizou-se a apresentação da norma dita padrão como outra variante a ser utilizada em determinadas situações, preservando a variante não padrão trazida pelos alunos, elemento identitário de seu universo sociocultural. Verificou-se que a apropriação da norma culta e o avanço linguístico dos alunos, em especial no que tange à textualidade, são possíveis por meio da tradução da Linguística Textual em prática de ensino de língua Portuguesa.
Marchiori, Daniela Gírio. « A mecânica da fratura elástica linear e o modelo coesivo na previsão do fraturamento de rochas ». Universidade de São Paulo, 1997. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-14112012-105517/.
Texte intégralThis present work has been developed aiming to verify the scale effect influence on the stress-strain curve form as well on the strength of two Brazilian rocks: Botucatu sandstone and basalt from Serra Geral Formation. Using samples of those rocks three point beam bending experiments have been made in with the crack displacement opening mouth was controlled. The experiments have been conducted using four different samples size. In the experiments no variation in the form of the force-displacement curve has been observed considering those chosen samples sizes. The rock strength variation for those samples is approximately the one predicted by the Linear Elastic Fracture Mechanics Theory. The force-displacement curves experimentally achieved were compared with two other curves obtained numerically, one using the Linear Elastic Fracture Mechanics Theory with FEM and other assuming the fictitious Cohesive Crack Model with BEM. It has been verified that among the two numerical procedures the Cohesive Crack Model gives better results and both give smaller displacements after the rupture.
Barros, Frederico Henrique Rodrigues. « O papel coesivo das conjuções na produção de textos escritos por aprendizes de inglês como língua estrangeira ». Universidade Católica de Pernambuco, 2008. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=405.
Texte intégralMost EFL students fail to elaborate an objective discourse and express themselves in a cohesive, clear and understandable way. We assume that part of the problem resides in their difficulty to use linking words to join simple and complex sentences. For this reason, we analyzed the role of conjunctions in written texts and how the EFL books deal with them. This research has been done with the participation of 27 EFL students who study at three different private English schools in the state of Pernambuco. As a result of this work, we conclude that there is a sort of limitation on the use of the conjunctions (linking words) in written texts produced by Brazilian EFL students. As a result of this research, we conclude that the use of conjunctions by the EFL students at these three schools is limited to: and but so because. This research work has been based on Text Linguistics, as well as the chart of conjunctions by Halliday and Hasan (1982). Its hoped that this work may call teacher and researchers attention to the importance of the cohesive ties in the teaching and learning of the English language
Figueiredo, Luiz Gustavo de. « O metodo dos elementos de contorno dual (DBEM) incorporando um modelo de zona coesiva para analise de fraturas ». [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257769.
Texte intégralDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: A avaliação da influêcia de um modelo coesivo de fratura no comportamento estrutural e a simulação de propagação de fraturas pré-existentes, com a Mecâica da Fratura Elástica Linear (MFEL), em problemas bidimensionais, usando o Método dos Elementos de Contorno Dual (DBEM), é o principal objetivo deste estudo. Problemas elásticos lineares em meio contínuo podem ser resolvidos com a equação integral de contorno de deslocamentos. O Método dos Elementos de Contorno Dual pode ser utilizado para resolver os problemas de fratura, onde a equação integral de contorno de forças de superfície é implementada em conjunto com a equação integral de contorno de deslocamentos. Elementos contínuos, descontínuos e mistos podem ser usados no contorno. Diferentes estrat?ias de posicionamento dos pontos de colocação são discutidas neste trabalho, onde os fatores de intensidade de tensão são avaliados com ténica de extrapolação de deslocamentos em fraturas existentes dos tipos: borda, inclinada e em forma de 'v¿. Um modelo coesivo é utilizado para avaliação de comportamento estrutural de um corpo de prova com fratura de borda segundo diferentes estratégias desenvolvidas: uma análise coesiva geral e uma análise coesiva iterativa, as quais são comparadas com o comportamento não coesivo. A força normal coesiva relaciona-se com o valor da abertura de fratura na direção normal na lei constitutiva na Zona de Processos Coesivos (ZPC). A simulação de propagação de uma fratura de borda existente e sua implementa?o num?ica no DBEM, sob deslocamento imposto, é realizada utilizando o critério da mínima tensão circunferencial. Palavras-chave: Método dos Elementos de Contorno; Métodos dos Elementos de Contorno Dual; Mecânica da Fratura Elástica Linear; Modelos Coesivos; Propagação de Fraturas
Abstract: An evaluation of the effect of the cohesive fracture model on the structural behavior and the crack propagation in pre-existing cracks with the Linear Elastic Fracture Mechanics (LEFM), for two dimensional problems, using the Dual Boundary Element Method (DBEM), is the main purpose of the present study. Linear elastic problems in continuum media can be solved with the boundary integral equation for displacements. The Dual Boundary Element Method can be used to solve fracture problems, where the traction boundary integral equation is employed beyond the displacement boundary integral equation. Conformal and non-conformal interpolations can be employed on the boundary. Different strategies for positioning the collocation points are discussed in this work, where the stress intensity factors are evaluated with the displacement extrapolation method to an existing single edge crack, central slant crack and central kinked crack. A cohesive model is used to evaluate the structural behavior of the specimen with a single edge crack under different strategies: a general cohesive analysis and an iterative cohesive analysis; which are compared with the non-cohesive behavior. The normal cohesive force is dependent of the crack opening value in the normal direction in the constitutive law of the Cohesive Process Zone (CPZ). A crack propagation of an existing single edge crack and its numerical implementation in DBEM, under constrained displacement, is analyzed using the maximum hoop stress criterion. Key Words: Boundary Element Method; Dual Boundary Element Method; Linear Elastic Fracture Mechanic; Cohesive Models; Propagation of Cracks
Mestrado
Estruturas
Mestre em Engenharia Civil
Schmid, Robert. « Geology of ultra-high-pressure rocks from the Dabie Shan, eastern China ». Phd thesis, [S.l.] : [s.n.], 2000. http://pub.ub.uni-potsdam.de/2001/0007/schmid_r.pdf.
Texte intégralSilva, Alvaro. « Os afixos no ensino/aprendizagem do hebraico língua estrangeira ». Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/8/8152/tde-09112007-153114/.
Texte intégralOne of the characteristic of Hebraic language, just like other semitic languages, is its construction from a structure composed, in general, for three main consonants. To obtain their texts there will be agglutinated affix consonants (suffix/prefix) in these radicals with functions of pronouns, prepositions, among others. Trying to get satisfactionally our objective, which is teaching of Hebraic language, we propose a method of teaching that makes easier the process of memorizing, looking for a context that make sense and the teach of grammatical structures that have the minimum of lexicon content, preparing the learner to make the most of the Hebraic language. One of the possibilities of making easier the lexicon Hebraic teaching can be observed in the characteristic of this language, based in formal structure of personal pronouns and some elements introduced in other grammatical categories, which are affixes. These Hebraic affixes are elements that give textual direction of almost all actions and verbal temporality. The article function used by these consonants will be the guide of our objective in order to show the permeability of this language and stimulate teachers and scientists to search elements that become easier the learning using affixes as beginning to understand the Hebraic text, mainly the biblical one, as instrumental language.
Santos, Patricia Aleixo dos. « Avaliação da resistência coesiva e da microdureza de uma resina composta polimerizada com fontes de luz halógena e LED ». Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/25/25131/tde-21062007-132249/.
Texte intégralThe aim of this study was to evaluate the tensile strength, through tensile tests, of a photopolymerizable composite resin (Filtek Z250 - 3M/ESPE), with variation of material\'s thickness, using an halogen light curing unit (Curing Light 2500 - 3M/ESPE - CL) and two light emitting diodes units (Ultraled - Dabi/Atlante - UL; Ultrablue IS - DMC - UB3 and UB6) with different power densities (130, 300, 600 and 640mW/cm2), as well as the influence of activation times (20, 40 and 60s) and, additionally, relate this data with the Knoop microhardness in that area corresponding to the fracture region of material. A number of 24 groups were stablished and a set of stainless matrix composed by two parts was used, with thickness of 1 and 2mm, to obtain the specimens. Next, the specimens were submitted to tensile tests in a Universal Testing Machine (Kratos), using a crosshead speed of 0,5mm/min and a 50Kg load cell until fracture. Tensile strength values were calculated in kgf/cm2 and translated into MPa. To microhardness test, the same matrix was used to obtain the specimens (24 groups - n=5), analyzing the hardness in the surfaces exposed and non-exposed to the light source. The Knoop microhardness test was made using a Shimadzu HMV-2 Microhardness Tester, at a static load of 50g at 30 seconds. The values obtained were submitted to three-way ANOVA and for individual comparison a Tukey test The aim of this study was to evaluate the tensile strength, through tensile tests, of a photopolymerizable composite resin (Filtek Z250 - 3M/ESPE), with variation of material\'s thickness, using an halogen light curing unit (Curing Light 2500 - 3M/ESPE - CL) and two light emitting diodes units (Ultraled - Dabi/Atlante - UL; Ultrablue IS - DMC - UB3 and UB6) with different power densities (130, 300, 600 and 640mW/cm2), as well as the influence of activation times (20, 40 and 60s) and, additionally, relate this data with the Knoop microhardness in that area corresponding to the fracture region of material. A number of 24 groups were stablished and a set of stainless matrix composed by two parts was used, with thickness of 1 and 2mm, to obtain the specimens. Next, the specimens were submitted to tensile tests in a Universal Testing Machine (Kratos), using a crosshead speed of 0,5mm/min and a 50Kg load cell until fracture. Tensile strength values were calculated in kgf/cm2 and translated into MPa. To microhardness test, the same matrix was used to obtain the specimens (24 groups - n=5), analyzing the hardness in the surfaces exposed and non-exposed to the light source. The Knoop microhardness test was made using a Shimadzu HMV-2 Microhardness Tester, at a static load of 50g at 30 seconds. The values obtained were submitted to three-way ANOVA and for individual comparison a Tukey test.
Agostinho, Paulo Cesar Primo. « Associação de chapas através da combinação dos métodos dos elementos de contorno e finitos considerando enrijecedores e crack coesivo ». Universidade de São Paulo, 1998. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-16032018-155138/.
Texte intégralThis work presents formulations for analysis of plate association, using the concept of sub-regions. It is also presented the substructure technique for the boundary elements method. The increasing in stiffiness in the continuous is considered by the combinations of the finite and boundary element methods. In this procedure the linear equation system becomes similar to the resulted by boundary element method. The formulation used also alows to simulate the slipping among rigid surfaces using plastic and simple viscous-plastic models of Coulomb type. This represents the descontinues in the forces and displacements among plates. It was also presented some numeric examples in order to validate the formulation used.
Cordeiro, Sérgio Gustavo Ferreira. « Formulações do método dos elementos de contorno aplicadas à análise elástica e à fratura coesiva de estruturas compostas planas ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-08042015-162639/.
Texte intégralThe present work deals the development of numerical formulations to evaluate the mechanical behaviour of plane composed structures, in the context of linear elasticity and nonlinear fracture mechanics. The proposed formulations are based on the Boundary Element Method (BEM), through its classical singular and hyper singular integral equations. The multi-region technique is adopted to couple the interfaces of non-homogeneous multiphase bodies. The BEM is a robust and accurate numerical technique to analyse fracture phenomena in solids. This numerical method presents a mesh dimensionality reduction, which makes easier the modelling of cracks surfaces. Besides, this dimensionality reduction also makes the treatment of interfaces in composed structures a less complex task. Considering the use of Kelvin fundamental solutions at the integrals equations, isotropic materials can be represent as parts of the composed structures. On the other hand, using Cruse & Swedlow fundamental solution it is also possible to deal with general anisotropic materials. At the composed structures, cracks can propagate along the materials interfaces and the cohesive crack model is responsible for the nonlinear structural behaviour of the quasi-brittle failures. The nonlinear system of equations at the fracture analyses is solved using two different algorithms for iterative resolution. The first always takes into account the structure elastic strength and, hence it is called Constant Operator (CO). On the other hand, the second is denominated Tangent Operator (TO) due to the fact that it considers strengths at the tangent directions of the nonlinear structural response. Therefore, convergence rates are faster when compared with the CO. As applications, composed structures were analysed with the developed formulations in linear elastic range. In addition, experimental fracture testes performed in concrete and wood specimens were also analysed. The confront of obtained results with the reference ones show that, the formulation was effective and accurate to evaluate the mechanical responses of composed structures in linear elastic range, and also to perform nonlinear quasi-brittle fracture tests.
Cameron, Kate. « Structure and function relationships in novel cohesin-dockerin complexes ». Doctoral thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2015. http://hdl.handle.net/10400.5/8126.
Texte intégralCohesin-dockerin interactions orchestrate the assembly of carbohydrate degrading multi-enzyme complexes produced by anaerobic bacteria termed cellulosomes. Type I dockerins typically display a dual binding mode which has been suggested to allow increased flexibility for cellulosome assembly. In contrast, structural work on type II dockerins suggests that they display a single binding mode. In this work structure function studies were developed in the cellulosomal systems of Clostridium thermocellum, Bacteroides cellulosolvens, and Acetivibrio cellulolyticus. The data provides novel structural and dynamic insights into the mechanism of substrate recognition by cellulosomes (Chapter 2). In addition, to understand the mechanism of cellulosome assembly in more elaborate cellulosomal systems, structural studies of novel type I and type II cohesin-dockerin complexes of B. cellulosolvens and A. cellulolyticus were developed. The crystal structure of a type I cohesin from B. cellulosolvens cell surface anchoring scaffoldin ScaB is reported (Chapter 3). This type I cohesin is highly similar to the type I cohesins from C. thermocellum and C. cellulolyticum and its cognate type I dockerin displays a dual binding mode. In Chapter 4, the structure of the type II X-dockerin from A. cellulolyticus in complex with a type II adaptor cohesin in two distinct orientations is described. The dockerin displays structural symmetry which is reflected by the presence of two essentially identical cohesin binding surfaces, suggesting that flexibility modulated by the dockerin dual binding mode is extended to type II complexes. In Chapter 5, the structure of a A. cellulolyticus type I cohesin-dockerin complex involved in cell surface attachment is described. Typical of type I cohesin-dockerin interactions this dockerin displays a dual binding mode, with a complex interface much more extensive than that observed in other type I complexes, resulting in an extremely tight interaction (Ka ~ 1012 M). Furthermore, data reveal that residues located at dockerin positions 12, 14 and 19 modulate the specificity of type I cohesin-dockerin interactions in A. cellulolyticus. In conclusion, this work demonstrates the importance of the dockerin dual binding mode to incorporate additional flexibility to cellulosome assembly and also polycellulosome assembly and cell surface attachment.
ABSTRACT - Relações estrutura-função em novos complexos coesina-doquerina. - As interacções coesina-doquerina são responsáveis pela organização de um complexo multi-enzimático concebido para a degradação de glúcidos complexos da parede celular vegetal e secretado por bactérias anaeróbias, denominado por celulossoma. As doquerinas do tipo I exibem geralmente um modo de ligação dupla, que tem sido apontada como responsável por uma maior flexibilidade no funcionamento do celulossoma. Pelo contrário, a estrutura de doquerinas do tipo II sugere um modelo simples de ligação. Neste trabalho são reportados estudos de estrutura-função nos sistemas celulossomais de Clostridium thermocellum, Bacteroides cellulosolvens e Acetivibrio cellulolyticus. Os resultados mostram que o mecanismo de reconhecimento da celulose - substrato principal do celulosoma, se faz de uma forma muito dinâmica através do fragmento N-terminal do complexo (Capítulo 2). Para compreender o mecanismo de funcionamento de sistemas celulossomais mais elaborados, procederam-se a estudos estruturais em complexos coesina-doquerina do tipo I e II, de B. cellulosolvens e A. cellulolyticus. A estrutura da coesina do tipo I da proteína ScaB do B. cellulosolvens foi determinada (Capítulo 3). Esta coesina mostrou ser topologicamente muito semelhante às do tipo I do C. thermocellum e do C. cellulolyticum e a doquerina por esta reconhecida apresenta um modo de ligação dupla. No Capítulo 4, a estrutura do módulo X-doquerina do tipo II de A. cellulolyticus em complexo com uma coesina do tipo II, presente numa proteína adaptadora, foi resolvida em duas orientações diferentes. O módulo X-doquerina exibe simetria estrutural que se traduz pela presença de duas superfícies de ligação à coesina praticamente idênticas, sugerindo que a flexibilidade impressa nesta doquerina é extensiva a complexos do tipo II. No Capítulo 5, a estrutura do complexo coesina-doquerina do A. cellulolyticus, que é responsável pela ligação do celulossoma à célula, foi resolvida. Típico das interacções coesina-doquerina do tipo I, esta doquerina exibe um modo de ligação dupla, possuindo, no entanto, uma interface de ligação mais extensa do que a observada em outros complexos do tipo I, resultando numa constante de afinidade extremamente elevada (Ka ~ 1012 M). Os dados revelam que os resíduos localizados nas posições 12, 14 e 19 da doquerina regulam a especificidade das interacções coesina-doquerina do tipo I em A. cellulolyticus. Em conclusão, este trabalho reforça a importância do modo de ligação dupla das doquerina para conferir flexibilidade à montagem do celulossoma e também na sua associação à superfície celular.
Gomes, Pedro Miguel Bule. « Divergent cellulosome architecture in rumen bacteria : structure and function studies in cohesin-dockerin complexes of Ruminococcus flavefaciens ». Doctoral thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2017. http://hdl.handle.net/10400.5/14242.
Texte intégralProtein-protein interactions play a vital role in many cellular processes as exemplified by the assembly of the cellulosome, a bacterial multi-enzyme complex that efficiently degrades cellulose and hemicellulose. Cellulosome assembly involves the high-affinity binding of type I enzyme-borne dockerins to repeated cohesin modules located on non-catalytic structural proteins termed scaffoldins. In addition, the complex is anchored into the bacterial surface through the binding of a scaffoldin type II dockerin to cell-bound cohesins. Initially, the architecture and organization of cellulosomes was thought to rely uniquely on type I and type II cohesin-dockerin interactions. It was recently suggested that cellulosomes from rumen bacteria are organized through different mechanisms involving a third type of cohesin-dockerin complexes. Thus, the genome of the major ruminal bacterium Ruminococcus flavefaciens FD-1 revealed a particularly elaborate cellulosome system that is assembled from a library of more than 200 different components through divergent cohesin-dockerin pairs. Providing structural insights for the specificity displayed by the increasing repertoire of cohesin-dockerin interaction is not only of fundamental importance but essential for the development of novel cellulosome based tools. The present work aimed to identify the molecular basis for the organization of R. flavefaciens cellulosome by dissecting the structural basis of cohesin-dockerin specificity in cellulosomes of rumen bacteria. The data revealed a collection of unique cohesin-dockerin interactions, supporting the functional relevance of dockerin classification in groups based on primary sequence similarity. In addition, R. flavefaciens cellulosome is assembled through a mechanism involving single but not dual-binding mode dockerins. This contrasts with the majority of the cellulosomes described to date where dockerins generally present two similar cohesin-binding interfaces, supporting a dual-binding mode. To illustrate this, the structures of two cohesin-dockerin complexes containing an Acetivibrio cellulolyticus dual-binding mode dockerin were solved. Finally, structural information was used to engineer a dockerin presenting a dual cohesin specificity, revealing the plasticity of the cohesin-dockerin platform to design novel protein-protein interactions.
RESUMO - Arquitetura celulossomal divergente em bactérias ruminais: estudos de estrutura e função em complexos coesina-doquerina do Ruminococcus flavefaciens - As interacções proteína-proteína desempenham um papel essencial em vários processos celulares, sendo exemplo disso a estruturação do celulosoma, um complexo bacteriano multienzimático altamente eficiente na degradação da celulose e hemicelulose. A montagem do celulosoma envolve interações de alta afinidade entre doquerinas do tipo I, presentes em enzimas, e os módulos coesina presentes em proteínas estruturais não catalíticas denominadas de escafoldinas. Adicionalmente, todo o complexo é ancorado à superfície bacteriana através da ligação de uma dockerina do tipo II, presente numa escafoldina, a coesinas ligadas à célula. Inicialmente, pensava-se que a arquitectura e organização dos celulosomas assentava exclusivamente em interacções coesina-doquerina do tipo I e II. Recentemente, foi sugerido que a microbiota ruminal contém bactérias produtoras de celulossoma com diferentes mecanismos de organização, envolvendo um terceiro tipo de complexos coesina-dockerina. O genoma da bactéria ruminal Ruminococcus flavefaciens FD-1, revelou um sistema celulossomal particularmente elaborado, montado a partir de uma biblioteca com mais de 200 componentes, através de complexos coesina-doquerina do tipo III. Estabelecer uma base estrutural para a especificidade exibida pelo crescente repertório de pares coesina-doquerina é não só fundamentalmente importante mas também essencial para o desenvolvimento de novas ferramentas com base no celulossoma. O presente trabalho teve como objetivo identificar a base estrutural para a especificidade coesina-doquerina do R. flavefaciens, permitindo descortinar os mecanismos por detrás da montagem dos celulosomas ruminais. Os dados obtidos revelaram uma colecção de interacções coesina-doquerina única, suportando a relevância funcional da classificação das doquerinas em grupos com base na homologia da sua estrutura primária. Mostraram ainda que o celulossoma do R. flavefaciens é montado através de um mecanismo envolvendo doquerinas com modo de ligação único mas não duplo. Isto contrasta com a maioria dos celulosomas descritos até à data, em que as doquerinas geralmente apresentam duas interfaces semelhantes de ligação à coesina, suportando um modo de ligação dupla. Tal é ilustrado pela estrutura de dois complexos coesina-doquerina do Acetivibrio cellulolyticus, envolvendo uma doquerina com modo de ligação dupla. Finalmente, esta informação estrutural foi usada para desenhar uma doquerina com dupla especificidade, mostranto a plasticidade da plataforma coesina-doquerina para o desenvolvimento de novas interações proteína:proteína.
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Pinto, Débora Sofia Costa. « Segunda circular-De limite a interface. Reconexão urbana, espaço público como elemento de ligação ». Master's thesis, Universidade de Lisboa. Faculdade de Arquitetura, 2013. http://hdl.handle.net/10400.5/6664.
Texte intégralSantos, Cristóvão Lucas dos. « Comportamento mecânico de ligações do tipo cavilha em estruturas de madeira ». Doctoral thesis, Universidade da Beira Interior, 2013. http://hdl.handle.net/10400.6/1889.
Texte intégralStagni, Andrea. « Dalla marginalizzazione alla rigenerazione delle aree interne : buone pratiche e prospettive ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Trouver le texte intégralMARTINEZ, BETANCOURT ELAINE. « Cohesión social en la actualización del Modelo cubano. Estudio de caso en el municipio Trinidad, provincia Sancti Spíritus, Cuba ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/325871.
Texte intégralLa tesis doctoral “Cohesión social en la actualización del Modelo cubano. Estudio de caso en el municipio Trinidad, provincia Sancti Spíritus, Cuba”, es resultado de tres años de debate teórico sobre la construcción de los procesos sociales y el desarrollo humano, de trabajo de campo multidisciplinario y, de prácticas metodológicas propias del Doctorado Internacional en Desarrollo Humano Sostenible, Universidad Milano Bicocca, Italia y el Proyecto “Caracterización de la apropiación que hace la población residente en Sancti Spíritus de la implementación de los Lineamientos, desde la cohesión social, formando parte de los nuevos emprendimientos laborales y socioproductivos en consejos populares, barrios y comunidades” (CALSS) de la Universidad “José Martí Pérez” de Sancti Spíritus, Cuba; con la finalidad de profundizar los supuestos relativos a la construcción de la cohesión social en una estrategia nacional de base socialista. Desde el Estudio de Caso -como estrategia de trabajo metodológica- se analiza la problemática con el propósito de debatir las diferentes visiones teóricas que sobre el tema se discuten en la academia, y contrastar, desde la perspectiva sociológica una experiencia real de cohesión social. Su objetivo general se orienta en el análisis de la cohesión social desde la descripción de las formas de interacción social que se manifiestan con el desarrollo de los emprendimientos en el territorio enunciado, ante el desafío que constituye el proceso de perfeccionamiento que se implementa en Cuba. La investigación aporta una sistematización de enfoques teóricos que predominan a nivel mundial sobre cohesión social y, una argumentación de los supuestos que la constituyen; presentes en la actualización del Modelo cubano y su intención de alcanzar una sociedad próspera y solidaria donde coexisten diferentes formas de gestión económica. A partir de la triangulación metodológica para la comprensión de las formas de interacción de los sujetos sociales se enfatiza en una perspectiva renovadora de los supuestos de la cohesión social, dígase, grupo de recomendaciones genéricas que enriquecen sus dimensiones; desde ahí el papel de los individuos como agentes de transformación social.