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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.
41

Uso de antibiótico, de probiótico e de homeopatia para frangos de corte criados em diferentes ambientes térmicos, inoculados ou não com Escherichia coli / Use of antibiotic, probiotic and homeopath for broilers reared under different thermal environments, inoculated or not with Escherichia coli

Boratto, Adriano José 21 February 2002 (has links)
Submitted by Nathália Faria da Silva (nathaliafsilva.ufv@gmail.com) on 2017-07-06T13:17:03Z No. of bitstreams: 1 texto completo.pdf: 225358 bytes, checksum: 008effb14c99d25d330c6324a9789f7c (MD5) / Made available in DSpace on 2017-07-06T13:17:03Z (GMT). No. of bitstreams: 1 texto completo.pdf: 225358 bytes, checksum: 008effb14c99d25d330c6324a9789f7c (MD5) Previous issue date: 2002-02-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Dois experimentos foram conduzidos em câmara climática para avaliar o efeito do uso de antibiótico, de probiótico e de homeopatia sobre o desempenho produtivo de frangos de corte submetidos a diferentes situações de desafio; em ambientes de conforto e estresse, inoculados ou não com Escherichia coli. Em cada experimento foram utilizados 672 frangos machos distribuídos em delineamento experimental inteiramente casualizado em esquema fatorial, com oito tratamentos (quatro aditivos x com ou sem inoculação) e seis repetições, com 14, 12 e 7 aves por unidade experimental, respectivamente, de acordo com os períodos 1 a 11, 12 a 21 e 22 a 42 dias de idade. Os tratamentos foram constituídos de: controle negativo (sem aditivo), antibiótico (virginiamicina + nitrovin), probiótico (meio de cultura de Lactobacilus acidophillus, Enterococcus faecium e Saccharomices cerevisiae) e homeopatia (nosódio de Escherichia coli). No primeiro experimento, as aves foram criadas em conforto térmico durante o período experimental de 1 a 42 dias. Observou-se que, no período de 1 a 11 dias, as aves que receberam probiótico apresentaram maior ganho de peso (GP) que as aves controle. No período de 1 a 21 dias, houve maior consumo de ração (CR) dos animais alimentados com probiótico, sendo que as aves tratadas com antibiótico apresentaram a melhor conversão alimentar. A inoculação da Escherichia coli reduziu a conversão alimentar (CA) das aves em 9 e 2%, respectivamente, para os períodos de 1 a 11 e 1 a 21 dias; a bactéria aumentou o peso relativo do coração, do fígado e dos intestinos e também diminuiu a relação vilo/cripta. No segundo experimento, as aves foram acondicionadas a 26oC no período inicial de 1 a 21 dias, e no conforto (25oC), no período de 22 a 42 dias. Observou-se que o probiótico aumentou o CR de 1 a 11 dias, sendo que nos períodos subseqüentes o desempenho das aves não foi influenciado por nenhum dos tratamentos. A inoculação da Escherichia coli diminuiu o GP e piorou a CA no período de 1 a 11 dias. Aos 11 dias, as aves que receberam homeopatia apresentaram maiores pesos absoluto e relativo de fígado, e aos 11, 21 e 42 dias, as aves tratadas com antibiótico tiveram o menor peso relativo de intestinos. A E.coli aumentou o peso relativo dos órgãos, principalmente o peso do fígado, e diminuiu a altura do vilo e aumentou a profundidade de cripta, reduzindo a relação vilo/cripta. As inoculações realizadas nos dois experimentos pioraram o desempenho das aves, mas não foram suficientemente intensas para provocar uma resposta mais efetiva dos tratamentos, sendo que os tratamentos antibiótico e probiótico melhoram o desempenho das aves apenas no período de 1 a 21 dias de idade. / Two experiments were carried out in acclimatized chambers to evaluate the use of antibiotic, probiotic and homeopathy on the broilers performance reared under different thermal environments, in comfort and stress environments, inoculated or not with Escherichia coli. Six hundred and seventy two male broilers were used in each experiment and allotted to a completely randomized design, in a factorial scheme, with eight treatments (four additives x inoculation or not) and six replicates, with 14, 12 and 7 birds per experimental box, respectively, according to the periods from 1 to 11, 12 to 21 and 22 to 42 days old. The treatments were constituted of: negative control (without additive), antibiotic (virginiamicine + nitrovin), probiotic (culture medium of Lactobacilus acidophillus, Enterococcus faecium and Saccharomices cerevisiae) and homeopathy (nosody of Escherichia coli). In the first experiment, the birds were reared under comfort environment, during the experimental period from 1 to 42 days. It ixwas observed that, from 1 to 11 days, the birds fed probiotic showed higher weight gain (WG) than the control birds. From 1 to 21 days, animals fed probiotic showed higher feed intake (FI) and the birds fed antibiotic showed the best feed:gain ratio. The inoculation of Escherichia coli reduced the feed:gain ratio (F/G) of birds in 9 and 2%, respectively, from 1 to 11 and from 1 to 21 days; the bacteria increased the relative weight of heart, liver and intestines and also decreased vilo/cripta ratio. In the second experiment, the birds were acclimatized at 26oC in the initial period (from 1 to 21 days), and in the comfort (25oC), from 22 to 42 days. It was observed that the probiotic increased FI from 1 to 11 days, and in the subsequent periods the birds performance was not affected by the treatments. The inoculation of Escherichia coli decreased WG and F/G from 1 to 11 days. At 11 days, the birds fed homeopathy showed higher absolute and relative weights of liver, and at 11, 21 and 42 days, the birds fed antibiotic showed the smaller relative weight of intestines. E.coli increased the relative weight of organs, meanly of liver, and decreased the villi height and increased the crypt depth, reducing the relation between villi height and crypt depth. The inoculations performed in both experiments decreased the birds performance, but were not strong enough so that a more effective answer of treatments could be obtained. The antibiotic and probiotic treatments increased the birds performance only from 1 to 21 days of age.
42

Diseño de un modelo de negocios para un promotor de exportaciones a China

Seguel Zamora, Marcelo Andrés January 2016 (has links)
Autor no autoriza el acceso a texto completo de su documento hasta el 25/5/2020. / Magíster en Gestión para la Globalización / Este proyecto de tesis pretende validar los servicios que ofrecerá La Casa de Chile , promotor de exportaciones que se enmarca en el contexto de la internacionalización de servicios entre China y Chile como principales actores. En los últimos años el crecimiento de China ha impulsado un gran dinamismo en el intercambio comercial con la economía chilena convirtiéndose en su principal socio comercial. Este mayor dinamismo abre una tremenda oportunidad para empresas de menor tamaño que se quieren beneficiar de este mayor intercambio comercial y buscan alternativas para su ingreso a tal mercado. El proyecto identifica un mercado potencial de 3.232 empresas Pyme que se encuentran activamente exportando, pero que aún no han llegado al territorio chino. También considera 442 empresas Pyme que ya se encuentran presentes en China, pero a través de intermediarios y representantes, ambos segmentos con un alto potencial de convertirse en clientes de este promotor. El análisis de la encuesta identifica como las principales propuestas de valor la innovación de los servicios ofrecidos, la infraestructura definida para el desarrollo del proyecto, la gestión de redes sociales chinas para clientes, y actividades de generación de demanda focalizada. También identifica la percepción de los clientes con respecto de estos servicios y su posterior intención de compra, donde se debe poner énfasis en promover la innovación de los servicios por sobre el concepto de un promotor de negocios local. El resultado del análisis financiero destaca la viabilidad del promotor de negocios, ante los dos modelos de venta planteados. Con una inversión inicial de USD 100.000 y una tasa de descuento aplicada de un 25%, ambos modelos difieren en la estimación de los ingresos y en la modalidad de cobro de los servicios. Los flujos estimados a 5 años arrojan un VAN de USD 64.770 para el caso del modelo de venta de paquetes, con una TIR de 45% y USD 37.808 para el modelo de servicio gestionado con una TIR de 32%. La sensibilización de estos flujos arroja que el impacto real del modelo de servicio gestionado varía sustancialmente de acuerdo a la cantidad de empresas atendidas y el número de consultores. Liberando la restricción de la capacidad instalada, el VAN aumenta a USD 130.625. Este resultado lleva finalmente a recomendar la ejecución del proyecto con la validación del modelo de negocio.
43

Reflexões sobre o Ministério Público Estadual Brasileiro: um estudo sobre o papel do promotor de justiça na defesa do direito à educação de qualidade

Sá, Itanieli Rotondo January 2014 (has links)
SÁ, Itanieli Rotondo. Reflexões sobre o Ministério Público Estadual Brasileiro: um estudo sobre o papel do promotor de justiça na defesa do direito à educação de qualidade. 2014. 213 f.: Dissertação (mestrado) - Universidade Federal do Ceará, Programa de Pós-Graduação em Direito, Fortaleza-CE, 2014. / Submitted by Natália Maia Sousa (natalia_maia@ufc.br) on 2015-06-11T16:07:21Z No. of bitstreams: 1 2014_dis_irsa.pdf: 1908217 bytes, checksum: 3fea15a99244ac42ffe683ef9129401a (MD5) / Approved for entry into archive by Camila Freitas(camila.morais@ufc.br) on 2015-06-16T16:16:46Z (GMT) No. of bitstreams: 1 2014_dis_irsa.pdf: 1908217 bytes, checksum: 3fea15a99244ac42ffe683ef9129401a (MD5) / Made available in DSpace on 2015-06-16T16:16:46Z (GMT). No. of bitstreams: 1 2014_dis_irsa.pdf: 1908217 bytes, checksum: 3fea15a99244ac42ffe683ef9129401a (MD5) Previous issue date: 2014 / This is an analysis of the right to “quality education” as a key component in the consolidation of citizenship and democratic institutions and a catalyst for the expansion of other rights. The study looks into the applicability of the notion of “commitment” to public education, extending the term beyond the legal sphere, and, in light of education as a fundamental right, provides definitions for “quality education” and other key concepts. To do so, we surveyed the measures taken by Brazilian authorities to evaluate the quality of education, and the main arguments pitched against them. Reflecting the quality policies adopted by the State, these measures play an important role in the current social debate on educational demands. The quality concepts recognized by the Summits of the Americas, the Brazilian Government and representatives of State Public Ministries seated in the COPEDUC (Permanent Education Commission) were analyzed. School Augustinho Brandão, a public high school considered a national reference in quality education, was selected for a case study in order to identify and help disseminate the values and practices which have most contributed to the schoolʼs renown. The position of the Public Ministry in each state with regard to the issue of quality education was appraised based on data collected from members of COPEDUC, and the possibility of adopting a quality standard for the use of the Public Ministry was discussed. The contribution of the Public Ministry to education-related cases brought before the Supreme Federal Court and made available online was evaluated to determine the profile of the demand and the major arguments and principles adduced. Overall, our findings prompt a deeper analysis on the subject of “quality education” and on the role played by the Public Ministry in the defense and promotion of this concept and right. The study also provides subsidies for quality education policy makers at national level and highlights the importance of quality education to the exercise of citizenship in a democratic state. / O objeto do presente estudo é a análise do direito à educação de qualidade, como instrumento imprescindível ao desenvolvimento da cidadania e a implementação de práticas democráticas, visto que, a partir dela é possível a expansão de outros direitos. O objetivo deste estudo foi aproximar o Direito ao compromisso com a educação, recorrendo a conceitos que fogem às práticas exclusivamente jurídicas, contextualizando o emprego de expressões como qualidade associados à educação e análise da educação como um direito fundamental. Procurou-se conhecer as medidas adotadas no Brasil, oficialmente, para aferição do padrão de qualidade e as principais críticas que pairam sobre este tipo de avaliação, pois além de serem reflexo da opção política de qualidade acatada pelo Estado, podem nortear as demandas da sociedade e pautar suas discussões. Conceituou-se educação de qualidade, analisando-se os conceitos de qualidade reconhecidos pela Cúpula das Américas, pelo Estado Brasileiro e concebidos pelos representantes dos Ministérios Públicos Estaduais, que integram a Comissão Permanente de Educação (COPEDUC), e que vem influindo na pauta de atuação institucional. Foi realizada pesquisa na Escola Estadual Augustinho Brandão, tida como referência nacional de qualidade de educação, com o escopo de averiguar as práticas que vem sendo adotadas e conhecer o que tem feito a diferença, como forma, de expandir conhecimentos sobre referida instituição e propagar suas boas práticas para disseminá-las. Fez-se um levantamento da atuação do Ministério Público, nos Estados brasileiros, com a coleta de dados junto aos promotores que integram a Comissão Permanente de Educação (COPEDUC), para ver como referida instituição tem se posicionado acerca de temática tão cara à sociedade e se é possível adotar um padrão de qualidade a ser seguido pelo Ministério Público. Ademais, foi realizada pesquisa jurisprudencial junto à página do Supremo Tribunal Federal acerca da atuação do Ministério Público nas ações que tenham pertinência com a temática da educação, a fim de averiguar o tipo de demanda que mais tem chegado à apreciação da corte de justiça referida e que fundamentos têm sido utilizados para sustentá-la. As pesquisas realizadas, de um modo geral, conduziram a uma reflexão mais profunda sobre o tema educação de qualidade e sua defesa pelo Ministério Público e possibilitam reflexão sobre a importância do envolvimento do órgão com a esfera qualitativa da educação. Ademais, visam trazer alguma luz para encaminhamento de questões atinentes à educação e implemento da importância da temática no cenário nacional como fundamental para consolidação do país como um Estado efetivamente Democrático de Direito.
44

Potencial biotecnológico de bactérias endofíticas de Himatanthus sucuuba

Nascimento, Aryana Pinheiro do, 92-99469-7377 10 February 2017 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-08-24T15:34:59Z No. of bitstreams: 2 Dissertação - Aryana P. Nascimento.pdf: 2567352 bytes, checksum: 9063d58d52a3f2ea23c51851087c23ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-08-24T15:35:15Z (GMT) No. of bitstreams: 2 Dissertação - Aryana P. Nascimento.pdf: 2567352 bytes, checksum: 9063d58d52a3f2ea23c51851087c23ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-24T15:35:15Z (GMT). No. of bitstreams: 2 Dissertação - Aryana P. Nascimento.pdf: 2567352 bytes, checksum: 9063d58d52a3f2ea23c51851087c23ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-10 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the search for sustainable alternatives of disease management, biocontrol agents as well as their antagonistic relations, appear as important source for the applied biological control. In this context, the use of endophytic microorganisms for biological control purposes has been extensively studied. They mainly comprise fungi and bacteria that inhabit the interior of plants without apparently causing damage to their hosts. Their ability to biocontrol can come from several mechanisms, such as the production of deleterious substances to phytopathogens or competing for space and nutrients. Indirectly, inducing systemic resistance in the host or by the production of growth promoting substances. In this sense, this work aimed at the isolation, biochemical and molecular characterization and the search for endophytic bacteria that act to reduce diseases such as anthracnose or are associated with the promotion of plant growth, reducing production costs and the environmental impact caused by the inputs Chemicals. A total of 416 bacterial isolates were obtained from H. sucuuba, representing 73.08% of the leaf, 10.10% of the petiole and 16.82% of the peel. From the total of 308 bacteria analyzed, 48.78% fixed atmospheric nitrogen, 83.77% were able to produce AIA and 96.42% solubilized inorganic phosphate. As for the in vitro antagonistic assay, 219 bacteria were selected by mass selection for the paired culture and thermostability tests. In the direct comparison, 68.49% were able to substantially inhibit the growth of phytopathogens by antibiosis, with different levels of toxicity to the challenging pathogens , With respect to thermostability, 33.79% of the lineages were highlighted because they were able to inhibit the growth of the phytopathogens of the three tropical hosts, revealing a great range of action, and, showing that the metabolites produced proved to be thermostable, maintaining their activities even after Autoclaving. / Na busca por alternativas sustentáveis de manejo de doenças, agentes de biocontrole bem como suas relações antagônicas, surgem como fonte importante para o controle biológico aplicado. Neste contexto, o emprego de micro-organismos endofíticos para fins de controle biológico vem sendo amplamente estudado. Eles compreendem, principalmente, fungos e bactérias que habitam o interior das plantas sem causar, aparentemente, danos aos seus hospedeiros. Sua capacidade de biocontrole pode advir de vários mecanismos, como a produção de substâncias deletérias a fitopatógenos ou competindo por espaço e nutrientes. Indiretamente, induzindo resistência sistêmica no hospedeiro ou pela produção de substâncias promotoras de crescimento. Neste sentido, este trabalho visou o isolamento, a caracterização bioquímica e molecular e a busca de bactérias endofíticas que atuem na redução de doenças como a antracnose ou estejam associados à promoção de crescimento vegetal, diminuindo os custos de produção e o impacto ambiental causados pelos insumos químicos. Foram obtidos 416 isolados bacterianos de H. sucuuba, representando 73,08% isoladas da folha, 10,10% do pecíolo e 16,82% da casca. Do total de 308 bactérias analisadas, 48,78% fixaram nitrogênio atmosférico, 83,77% foram capazes de produzir AIA e 96,42% solubilizaram fosfato inorgânico. Quanto ao ensaio de antagonismo in vitro, 219 bactérias foram selecionadas por seleção massal para os testes de cultura pareada e termoestabilidade, no confronto direto 68,49% conseguiram inibir substancialmente o crescimento dos fitopatógenos agindo por antibiose, com diferentes níveis de toxicidade aos patógenos desafiantes, quanto à termoestabilidade 33,79% das linhagens destacaram-se pois conseguiram inibir o crescimento dos fitopatógenos das três hospedeiras tropicais, revelando um grande espectro de ação, e, mostrando que os metabólitos produzidos demonstraram-se termoestáveis, mantendo suas atividades mesmo após a autoclavagem.
45

Produção de proinsulina recombinante em Pichia pastoris utilizando o promotor do gene PGK

Assunção, Enedina Nogueira de 26 September 2015 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-10-03T12:39:39Z No. of bitstreams: 1 Tese - Enedina Nogueira de Assunção.pdf: 3908952 bytes, checksum: 3e60d5d0a0af7d037587c69426e344bb (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-10-03T12:39:58Z (GMT) No. of bitstreams: 1 Tese - Enedina Nogueira de Assunção.pdf: 3908952 bytes, checksum: 3e60d5d0a0af7d037587c69426e344bb (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-10-03T12:40:16Z (GMT) No. of bitstreams: 1 Tese - Enedina Nogueira de Assunção.pdf: 3908952 bytes, checksum: 3e60d5d0a0af7d037587c69426e344bb (MD5) / Made available in DSpace on 2016-10-03T12:40:16Z (GMT). No. of bitstreams: 1 Tese - Enedina Nogueira de Assunção.pdf: 3908952 bytes, checksum: 3e60d5d0a0af7d037587c69426e344bb (MD5) Previous issue date: 2015-09-26 / According to the World Health Organization (WHO), diabetes mellitus is expected to reach 333 million by 2025 and around 2030 is going to be the second cause of death in Latin America. Therefore, an insulin production increasing becomes a need to meet future market demands. The heterologous expression system in Pichia pastoris have been increasingly used and has proven to be an attractive alternative for over expressing human genes for biotechnological purposes. Thus, this work has as main objective to produce human proinsulin by P. pastoris using a PGK gene promoter. A1 gene codes for the insulin precursor and was chemically synthesized with optimized codons for P. pastoris. This gene was cloned into expression vector / secretion under control of PGK P. pastoris promoter and integrated into the genome of P. pastoris GS115. Transformant clones were selected for increased zeocin production and from dot-blotting. The production of recombinant proinsulin was performed in YPD liquid in shake flasks at 30 ° C, 180 rpm. The supernatant was clarified by centrifugation, and detection of recombinant proteins by ELISA, electrophoresis in denaturing polyacrylamide gel, Western-blotting and finally chromatography for size exclusion. Best conditions for expression / secretion of proinsulin were established through statistical experimental design detecting the expression level by ELISA. The amount of pre-proinsulin mRNA was determined from two samples of two contrasting conditions of A140 clone with the highest and lowest production of proinsulin using Real-Time PCR (qPCR). As results, the recombinant clones that had higher resistance to Zeocin also showed more intense positive signs in the dot-blotting. Proinsulin coding sequence (A1) was efficiently expressed in P. pastoris and secreted into the cell culture supernatant, with molecular weight of approximately 7.5 kDa. The A140 clone showed significant productivity in production level within 48 to 72 hours after the improvement of the YPD culture medium showed level of 0.83 g/L of insulin expression at 72 hours, for total biomass of about 50g / L. High levels of proinsulin expression with PGK promoter using P. pastoris as host make this heterologous expression attractive for human proinsulin production as well as other industrial proteins. / De acordo com os indicadores da Organização Mundial de Saúde (OMS) o diabetes mellitus deve alcançar 333 milhões de pessoas em 2025 no mundo e em 2030 na América Latina será a segunda causa de morte, por isso o aumento da produção de insulina torna-se uma necessidade para suprir as futuras demandas de mercado. Os sistemas de expressão em leveduras tipo Pichia pastoris tem sido cada vez mais utilizados e tem-se mostrado como atraentes alternativas para a expressão de proteínas para fins industriais. Dessa forma, este trabalho tem como objetivo principal a produção de proinsulina humana por Pichia pastoris utilizando o promotor do gene PGK. O gene A1 que codifica o precursor da insulina foi sintetizado quimicamente com codóns otimizados para a expressão em P. pastoris. Esse gene foi clonado em vetor de expressão/secreção sob controle do promotor PGK de P. pastoris e integrado no genoma de P. pastoris GS115. A produção de proinsulina recombinante foi realizada em meio líquido YPD em frascos agitados a 30°C, a 180 rpm. A análise da proinsulina expressa em P. pastoris foi realizada por eletroforese em gel desnaturante de poliacrilamida e Western-blotting e mostrou massa molecular de aproximadamente 7,5 kDa. O clone recombinante A140 que apresentou maior resistência a zeocina e sinal positivo mais intenso no imunodot-blotting foi utilizado para estabelecer condições melhores de expressão/secreção de proinsulina em planejamento fatorial estatístico experimental. As condições de cultivo que se mostraram melhores para a produção da proinsulina foram: composição do meio de cultivo (dextrose 7,5%, extrato de levedura 1% e peptona 0,15%), temperatura de 25°C e pH do meio igual a 7,0. O clone A140 nas melhores condições de cultivo atingiu biomassa total de 50g/L e nível de expressão de insulina de 0,83g/L em 72 horas de cultivo. A expressão de proinsulina em altos níveis utilizando o promotor PGK em P. pastoris faz esse sistema de expressão atrativo para produção da proinsulina humana e outras proteínas de interesse industrial.
46

Local heat transfer coefficients in an annular passage with flow turbulation

Steyn, Rowan Marthinus January 2020 (has links)
In this experimental and numerical investigation, the use of flow turbulation was considered as a method to increase local heat transfer coefficients in annular heat transfer passages. Experimental data was obtained for cases with and without inserted ring turbulators within a horizontal annular test section using water for average Reynolds numbers ranging from 2000 to 7500 and average Prandtl numbers ranging from 6.73 to 6.79. The test section was heated uniformly on the inner annular wall and had a hydraulic diameter of 14.8mm, a diameter ratio (inner wall diameter to outer wall diameter) of 0.648, and a length to hydraulic diameter ratio of approximately 74. A set of circular cross sectioned ring-type turbulators were used which had a thickness of 1mm, a ring diameter of 15.1mm and a pitch of 50mm. It was found that the presence of the flow turbulators increased the average Nusselt number by between 33.9% and 45.8%. The experimental tests were followed by numerical simulations to identify the response in the heat transfer coefficient by changing the geometry of the turbulators. For this, the turbulator diameters were ranged from 0.5 mm to 2 mm, and the gap size (between the inner wall and a turbulator ring) ranged from 0.125 mm to 4 mm at a pitch of 50 mm. The results showed that the use of turbulators increased the Nusselt numbers by a maximum of 34.8% and that the maximum can be achieved for a turbulator diameter of 2 mm and a gap size of 0.25 mm, for all the Reynolds numbers tested. From the numeric determined pressure drop values it was found that the smaller gap size had the lowest pressure drop and the smallest turbulators also produced the lowest pressure drop. / Dissertation (MEng)--University of Pretoria 2020 / South African Centre for High Performance Computing (CHPC) / Mechanical and Aeronautical Engineering / MEng / Unrestricted
47

Software unterstützte Analyse von regulatorischen Elementen in Promotoren mittels AIModules / Software backed Analysis of regulatory Elements of Promoters with AIModules

Aydinli, Muharrem January 2021 (has links) (PDF)
Die Regulation der Genexpression steht am Anfang vieler zellbiologischer Prozesse wie beispielsweise dem Zellwachstum oder der Differenzierung. Gene werden an Promotoren transkribiert, wobei ein Promotor selbst aus vielen logischen Einheiten aufgebaut ist, den Transkriptionsfaktorbindestellen (TFBSs). Diese können sehr nah beieinander liegen, aber auch weit entfernt voneinander sein. Sie werden spezifisch von Transkriptionsfaktoren (TFs) gebunden, die die Transkritptionsrate z.B. verstärken (Enhancer) oder schwächen (Silencer) können. Zwei oder mehr dieser TFBSs mit bestimmtem Abstand werden als "Module" zusammengefasst, die über Spezies hinweg konserviert sein können. Typischerweise findet man Module in Zellen mit einem Zellkern. Spezies mit gemeinsamen Modulen können ein Hinweis auf die gemeinsame phylogenetische Abstammung darstellen, aber auch gemeinsame Funktionsmechanismen von TFs über Gene hinweg aufdecken. Heutzutage sind verschiedene Anwendungen verfügbar, mit denen nach TFBSs in DNA gesucht werden kann. Zum Zeitpunkt des Verfassens dieser Arbeit sind aber nur zwei kommerzielle Produkte bekannt, die nicht nur TFBSs, sondern auch Module erkennen. Deshalb stellen wir hier die freie und quelloffene Lösung "AIModules" vor, die diese Lücke füllt und einen Webservice zur Verfügung stellt, der es erlaubt nach TFBSs sowie nach Modulen auf DNA- und auf RNA-Abschnitten zu suchen. Für die Motivesuche werden entweder Matrizen aus der Jaspar Datenbank oder Matrizen vom Anwender verwendet. Darüberhinaus zeigen wir, dass unser Tool für die TF Suche nur Sekunden benötigt, wohingegen conTraV3 mindestens eine Stunde für dieselbe Analyse braucht. Zusätzlich kann der Anwender bei unserem Tool den Grad der Konserviertheit für TFs mit angeben und wir zeigen, dass wir mit unserer Lösung, die die Jaspar Datenbank heranzieht, mehr Module finden, als ein kommerziell verfügbares Produkt. Weiterhin kann mit unserer Lösung auch auf RNA-Sequenzen nach regulatorischen Motiven gesucht werden, wenn der Anwender die dafür nötigen Matrizen liefert. Wir zeigen dies am Beispiel von Polyadenylierungsstellen. Zusammenfassend stellen wir ein Werkzeug vor, das erstens frei und quelloffen ist und zweitens entweder auf Servern veröffentlicht werden kann oder On-Site auf einem Notebook läuft. Unser Tool erlaubt es Promotoren zu analysieren und nach konservierten Modulen sowie TFBSs in Genfamilien sowie nach regulatorischen Elementen in mRNA wie z.B. Polyadenylierungsstellen oder andere regulatorische Elemente wie beispielsweise Enhancern oder Silencern in genomischer DNA zu suchen. / Regulation of gene expression is at the root of many processes in cellular biology such as cell growth and differentiation. Promotors are the starting points for the transcription of a gene. The promotor itself consists of transcription factor binding sites (TFBSs) which can be closely located or vastly apart. They are recognized and bound by transcription factors (TFs) which themselves can e.g. enhance or silence the transcribing process by the RNA polymerases. Two or more of those transcription factor binding sites within a certain range are called a "module". Typically, those are found in cells with a nucleus and they may be conserved throughout species. The knowledge of modules may indicate a phylogenetic relationship among species but may also provide insight into the concerted actions of TFs on different genes. Currently there are a number of tools available that can enable a user to find TFBSs on DNA. But at the time of assembling this thesis, there are only two commercial software products available, that can not only detect TFs but also modules. Therefore, we present a free and open source solution that fills this gap by providing a web service that searches for TFBSs and modules on DNA as well as RNA stretches, called "AIModules". For that, matrices from the Jaspar database or user input matrices are used for motif discovery. Additionally, we show that our tool does TF analysis in seconds, whereas tools like conTraV3 took at least an hour. Furthermore, for the module search the user can specify the degree of conservation of the TFs. We show that with our solution using the JASPAR database we find more modules than a commercially available tool. Moreover, with our application RNA stretches can also be searched for regulatory motifs if suitable matrices are provided. We illustrate this for polyadenylation sites. Thus, our solution is free and open source, and can be deployed on servers as well as provided on-site on a notebook. We provide a tool to analyze promotors and search for conserved modules as well as common TFBSs in gene families, search for regulatory elements in mRNA such as polyadenylation sites or other regulatory elements such as enhancers or silencers in genomic DNA.
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Die Regulation des Chemokinrezeptors CXCR4 durch Chemotherapeutika in Myelomzelllinien / The regulation of chemokinreceptor CXCR4 by chemotherapeutics in myeloma cell lines

Widmaier, Louis January 2023 (has links) (PDF)
Untersucht wurde der Einfluss mehrerer Chemotherapeutika auf den Chemokinrezeptor CXCR4 in Myelomzelllinien auf Ebene des Promotors, der mRNA und der Rezeptorverteilung, wobei drei Substanzen (Etoposid, Bortezomib und Dexamethason) als potenzielle Suppressoren des Promotors ausgemacht werden konnten. Abhängig vom Myelom-Zelltyp und der Dosierung können so evtl. Rückschlüsse auf die beobachtete Suppression von CXCR4 bei erkrankten Patienten mit hoher CXCR4-Aktivität (hier: Malignes Myelom) durch die begleitende Chemotherapie gezogen werden, welche eine Diagnostik und Therapie bei diesen Patienten erschwert. Hintergrund: Hintergrund für diese Arbeit waren Beobachtungen in klinischen Fallstudien von Lapa et al. am Universitätsklinikum Würzburg, die sich auf CXCR4 bezogen, welches u.a. bei Patienten mit Multiplem Myelom überexprimiert wird und dadurch bereits als Target für Diagnostik und Therapie in der Klinik Anwendung findet. Dabei konnte bei PET-CT Untersuchungen in der Nuklearmedizin beobachtet werden, dass es durch die begleitende Chemotherapie der Patienten zu einer Suppression des markierten CXCR4-Signals kam, so dass es nicht mehr zur Verlaufsbeobachtung und vor allem nicht mehr zur Radiotherapie und Therapiekontrolle verwendet werden konnte. Um den Einfluss und mögliche Interaktionen der Chemotherapeutika auf CXCR4 zu untersuchen, war es Ziel dieser Arbeit, ein vergleichbares Szenario in-vitro nachzustellen und Einflüsse messbar zu machen, um so mögliche Ansätze und Verbesserungsvorschläge für die klinische Anwendung zu liefern. Methoden/Ergebnisse: Hierfür wurden im ersten Teil INA-6 (Myelomzellen) und Mesenchymale Stammzellen (MSC) kultiviert, in Ko-Kultur gebracht und nach einer bestimmten Zeit wieder getrennt, um anschließend den gegenseitigen Einfluss in Bezug auf CXCR4 zu messen. Zudem wurde der Einfluss von Dexamethason untersucht. Es zeigte sich eine enge Bindung zwischen INA-6 und MSC sowie eine hohe CXCR4-Aktivität bei INA-6, jedoch konnte keine Induktion der CXCR4-Aktivität in MSC durch INA-6-Kontakt oder Dexamethason quantifiziert werden. Die Immunzytologie erwies sich aufgrund einer schweren Anfärbbarkeit von CXCR4 – auch mit verschiedensten Antikörpern und sogar Liganden-gekoppeltem Farbstoff– als kaum auswertbar, wobei eine Darstellung von CXCR4 generell aber gelang. Der CXCR4-Promotor wurde mittels Software genauer analysiert, wobei einige relevante Bindestellen, u.a. für Glukokortikoide und NFkB gefunden wurden. Die Herstellung eines CXCR4- pGl4.14-Promotor-Konstrukts war erfolgreich, ebenso dessen Einschleusung in Myelomzellen. Auch gelang die Herstellung stabiler transfizierter INA-6, sodass mit diesen anschließend konstantere Ergebnisse erzielt werden konnten. Im größten Teil der Arbeit wurden geeignete Chemotherapeutika-Konzentrationen ermittelt und in Viabilitäts- und Apoptose-Versuchen überprüft. Die Stimulationsversuche mit diesen zeigten variable Effekte abhängig vom Zelltyp (INA-6, MM1S), jedoch konnten Bortezomib, Etoposid und Dexamethason konzentrationsabhängig als starke Suppressoren der CXCR4-Aktivität ausgemacht werden, was sich v.a. auf Ebene der Promotoraktivität – gemessen mittels Luciferase - zeigte. Interpretation: In-vitro konnten somit drei potenzielle Suppressoren der CXCR4-Aktivität ausgemacht werden: Etoposid, Bortezomib und Dexamethason. Zumindest beim INA-6-Zelltyp fiel dieser Effekt deutlich aus, wobei in der Klinik der entsprechende Zelltyp sowie die Dosierung der Medikamente berücksichtigt werden müssen. Hinzu kommen weitere Einflussfaktoren des menschlichen Körpers, die nicht berücksichtig werden konnten. Die genauen Mechanismen der Suppression könnten sich aus den Bindestellen des Promotors erklären, die von uns analysiert wurden, aber auf die in weiteren Arbeiten noch näher eingegangen werden muss. / The influence of several chemotherapeutic agents on the chemokine receptor CXCR4 in myeloma cell lines at the level of the promoter, the mRNA and the receptor distribution was examined, whereby three substances (etoposide, bortezomib and dexamethasone) could be identified as potential suppressors of the promoter. Depending on the cell type and the dosage, conclusions can be drawn about the observed suppression of CXCR4 in patients with diseases with high CXCR4 activity (here: multiple myeloma) due to the accompanying chemotherapy, which impairs theranostic applications like diagnostic imaging using PET/CT and may in particular abolish the chances of radiotherapeutic intervention in these patients. Background: The background for this work were observations in clinical case studies by Lapa et al. at the University Hospital Würzburg, which referred to CXCR4, which is overexpressed in patients with multiple myeloma and is therefore already used as a target for diagnostics and therapy in the clinic. During PET-CT examinations in nuclear medicine, it could be observed that the accompanying chemotherapy of the patients led to a suppression of the marked CXCR4 signal, which is why it could no longer be used for monitoring the follow-up, but also was lost as a radiotherapeutic target. In order to investigate the influence and possible interactions of chemotherapeutic agents on CXCR4, the aim of this work was to simulate a comparable scenario in vitro and to make influences measurable in order to provide possible approaches and suggestions for improvement for clinical application. Methods/Conclusions: For this purpose, INA-6 (myeloma cells) and mesenchymal stem cells (MSC) were cultivated in the first part, brought into co-culture and separated again after a certain time in order to then measure the mutual influence with regard to CXCR4 expression. The influence of dexamethasone was also examined. There were intensive contacts between INA-6 and MSC and high CXCR4 activity in INA-6, but no induction of CXCR4 activity in MSC by INA-6 or dexamethasone could be quantified. The immunocytology turned out to be difficult due to the difficulty of staining CXCR4 - even with a wide variety of antibodies and ligand-coupled dyes - although CXCR4 was generally able to be represented. The CXCR4 promoter was analyzed in more detail using the Genomatix software, and some relevant binding sites, including response elements for glucocorticoids and NFkB, were found. The production of a CXCR4-pGl4.14 luciferase-reporter construct was successful, as was its introduction into myeloma cells. The production of stably transfected INA-6 was also successful, so that more constant results could then be achieved. In a large part of the work, suitable chemotherapeutic concentrations were determined and checked in viability and apoptosis tests. The stimulation experiments with these showed variable effects depending on the cell type (INA-6, MM1S). However, depending on the concentration, bortezomib, etoposide and dexamethasone could be identified as strong suppressors of CXCR4 activity, which was particularly evident at the level of activity of our luciferase-reporter construct. Interpretation: Overall, three potential suppressors of CXCR4 activity could be identified in-vitro: etoposide, bortezomib and dexamethasone. At least with the INA-6 cell type, this effect was clear, although the corresponding cell type and the dosage of the medication must be taken into account in the clinic. In addition, there may be other influencing factors of the human organism in vivo that could not be considered. The exact mechanisms of suppression could be explained by the binding sites of the promoter, which we analyzed, but which will have to be discussed in more detail in further work.
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Influencia del comportamiento colaborativo en la construcción de edificios residenciales de promoción privada en España. Comparativa con la experiencia Norteamericana

Sanz Benlloch, María Amalia 21 March 2016 (has links)
[EN] Traditional project delivery methods in the construction industry clearly separate the design and construction phases. In Spain, due to the current legislation and practice in both building and civil engineering works, this traditional project delivery method is essentially used. Many authors criticize the traditional delivery method due to cost overruns, schedule delays and lower quality for public and private facility owners. In view of this background, the main objectives of the research are to analytically study the influence of integration and collaborative team behavior in the success of the design-construction process of private residential buildings in Spain. Additionally, this research will compare the results with a similar study conducted in the United States. In this manner, the differences between the two countries can be highlighted, and measures to adapt best practices from the United States to Spain, and vice versa, can be adopted. The scope of the study is limited to the design and construction phases of the building life cycle. In this context, the project team comprises those participants that have the most importance in the design and construction phases of the building (owner, designer, representative of the owner, construction site manager, and key specialty trade subcontractors). In the research, the unit of analysis is the construction project, collecting information from a set of residential building projects privately developed in Spain. The data collection process started jointly in Spain and the United States with a comprehensive literature review and input from a panel of industry professionals. The process established the scope of the investigation and the preparation of the data collection questionnaire. Valid data from 31 residential building projects was obtained by structured interviews with the owner and constructor from each project. Data were analyzed through descriptive and inferential statistics (univariate and multivariate). Later, a multiple case-study was used to validate and explore the quantitative results. Finally, results from the Spanish research were compared with a similar sample of the United States. This comparison identified the differences and similarities between project delivery and integration in the two countries from both the traditional and alternative delivery methods. The study results showed that owner organizations with high levels of integration positively influenced both team performance and project success. Owner's organization, team behavior and project experience were found to be the key factors that had a positive influence on the project success. These key factors also positively influenced team behavior. The research did not identify a single factor that could predict project success. Rather, a combination of these variables is necessary to increase the likelihood of success. It was also found that the Spanish projects in this study, compared with the similar traditionally delivered projects in the United States, finished with lower deviations in cost but higher deviations in schedule. In Spain, the project teams had higher values in group cohesion, compared with those from the United States. However, in the United States, project teams had more integrated practices. In both countries, the traditionally delivered project had lower values of cohesion and integration than other more innovative strategies in the United States. / [ES] El modelo de contratación tradicional en el sector de la construcción diferencia claramente las fases de diseño y construcción sin integrarlas. En España, debido a la legislación existente y a la costumbre, tanto en edificación como en obra civil, se utiliza básicamente este sistema tradicional de contratación. Este modelo ha sido criticado por numerosos autores debido al sobrecoste, aumento de plazos y merma de la calidad que supone para el promotor, público o privado. A la vista de estos antecedentes, los objetivos principales de la investigación consisten, por una parte, en estudiar analíticamente la influencia de la integración y el comportamiento colaborativo del equipo en el éxito del proceso proyecto-construcción de edificios residenciales de promoción privada en España y, por otra parte, comparar los resultados obtenidos con una investigación similar realizada en Estados Unidos. De este modo, pueden conocerse las diferencias entre ambos países y pueden proponerse medidas para adaptar las mejores prácticas obtenidas del estudio norteamericano al caso español y viceversa. El alcance del estudio se limita exclusivamente a las fases de diseño y construcción del ciclo de vida de un edificio. En este mismo contexto, se entiende por equipo a los participantes que tienen mayor relevancia en las fases de diseño y construcción del edificio (promotor, arquitecto, director de obra, constructor, y los subcontratistas de los trabajos más especializados). En la investigación la unidad de análisis es la obra, obteniéndose la información de un conjunto de obras de edificación residencial de promoción privada en España. La investigación se inició conjuntamente en España y Estados Unidos con una revisión exhaustiva de la literatura, y un análisis por parte de un panel de expertos, que permitieron determinar el alcance de la investigación y la elaboración del cuestionario de recogida de datos. Se obtuvieron datos válidos de 31 obras, mediante entrevistas estructuradas al promotor y constructor de cada una de ellas. Los datos se analizaron mediante técnicas estadísticas (descriptivas, de correlación y multivariantes). Posteriormente, se llevó a cabo un estudio de casos múltiple que permitieron validar los resultados cuantitativos obtenidos. Por último, se compararon los resultados de la investigación en España con una muestra similar de Estados Unidos. Esta comparación permitió identificar las diferencias y similitudes entre ambos países, aunque sea desde el punto de vista del enfoque tradicional de contratación. El estudio concluyó que una organización del promotor con niveles altos de integración influía positivamente tanto en el comportamiento del equipo como en el éxito de la obra. La organización del promotor, el comportamiento del equipo y la experiencia, podrían considerarse como los factores clave que tienen una influencia positiva en el éxito de la obra y también contribuían directamente a los comportamientos positivos del equipo. No obstante, no se identificó un único factor que pudiera predecir el éxito de la obra; más bien, sería necesaria una combinación de variables para aumentar la probabilidad de éxito. También se detectó que las obras analizadas en España, en comparación con las obras analizadas en Estados Unidos para el sistema de contratación tradicional, finalizaron con desviaciones inferiores de coste pero superiores en plazo. En España, los equipos de trabajo presentaron valores más altos en la cohesión del grupo, en comparación con los de Estados Unidos. Sin embargo, en Estados Unidos los equipos llevaron a cabo prácticas más integradas que en España. En ambos países, el sistema de contratación tradicional presentó valores más bajos de cohesión e integración que en otras estrategias más innovadoras analizadas en la investigación norteamericana. / [CA] El model de contractació tradicional en el sector de la construcció diferència clarament les fases de disseny i construcció sense integrar-les. A Espanya, a causa de la legislació existent i al costum, tant en edificació com en obra civil, s'utilitza bàsicament este sistema tradicional de contractació. Este model ha sigut criticat per nombrosos autors a causa del sobrecost, augment de plaços i reducció de la qualitat que suposa per al promotor, públic o privat. A la vista d'estos antecedents, els objectius principals de la investigació consistixen, d'una banda, a estudiar analíticament la influència de la integració i el comportament col·laboratiu de l'equip en l'èxit del procés projecte-construcció d'edificis residencials de promoció privada a Espanya i, d'altra banda, comparar els resultats obtinguts amb una investigació semblant realitzada als Estats Units. D'esta manera, poden conéixer-se les diferències entre ambdós països i poden proposar-se mesures per a adaptar les millors pràctiques obtingudes de l'estudi nord-americà al cas espanyol i viceversa. L'abast de l'estudi es limita exclusivament a les fases de disseny i construcció del cicle de vida d'un edifici. En este mateix context, s'entén per equip als participants que tenen major rellevància en les fases de disseny i construcció de l'edifici (promotor, arquitecte, director d'obra, constructor, i els subcontractistes dels treballs més especialitzats). En la investigació la unitat d'anàlisi és l'obra, obtenint-se la informació d'un conjunt d'obres d'edificació residencial de promoció privada a Espanya. La investigació es va iniciar conjuntament a Espanya i Estats Units amb una revisió exhaustiva de la literatura, i una anàlisi per part d'un panell d'experts, que van permetre determinar l'abast de la investigació i l'elaboració del qüestionari d'arreplega de dades. Es van obtindre dades vàlids de 31 obres, per mitjà d'entrevistes estructurades al promotor i constructor de cada una d'elles. Les dades es van analitzar per mitjà de tècniques estadístiques (descriptives, de correlació i multivariants). Posteriorment, es va dur a terme un estudi de casos múltiple que van permetre validar els resultats quantitatius obtinguts. Finalment, es van comparar els resultats de la investigació a Espanya amb una mostra semblant dels Estats Units. Esta comparació va permetre identificar les diferències i similituds entre ambdós països, encara que siga des del punt de vista de l'enfocament tradicional de contractació. L'estudi va concloure que una organització del promotor amb nivells alts d'integració influïa positivament tant en el comportament de l'equip com en l'èxit de l'obra. L'organització del promotor, el comportament de l'equip i l'experiència podrien considerar-se com els factors clau que tenen una influència positiva en l'èxit de l'obra i també contribuïen directament als comportaments positius de l'equip. No obstant això, no es va identificar un únic factor que poguera predir l'èxit de l'obra; més aïna, seria necessària una combinació de variables per a augmentar la probabilitat d'èxit. També es va detectar que les obres analitzades a Espanya, en comparació amb les obres analitzades als Estats Units per al sistema de contractació tradicional, van finalitzar amb desviacions inferiors de cost però superiors en plaç. A Espanya, els equips de treball van presentar valors més alts en la cohesió del grup, en comparació amb els dels Estats Units. No obstant això, als Estats Units els equips van dur a terme pràctiques més integrades que a Espanya. En ambdós països, el sistema de contractació tradicional va presentar valors més baixos de cohesió i integració que en altres estratègies més innovadores analitzades en la investigació nord-americana. / Sanz Benlloch, MA. (2016). Influencia del comportamiento colaborativo en la construcción de edificios residenciales de promoción privada en España. Comparativa con la experiencia Norteamericana [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61960
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Vlastnosti expresních vektorů pro Corynebacterium glutamicum a jejich využití při studiu faktorů sigma RNA polymerasy / Characteristics of expression vectors for Corynebacterium glutamicum and their use for studies of sigma factors of RNA polymerase

Dvořáková, Pavla January 2017 (has links)
The aim of the thesis was to characterize chosen expression vectors used in biotechnologically important bacterial species, Corynebacterium glutamicum, and to test their use in studies of promoter activity control by sigma factors of RNA polymerase. Different properties of these vectors (level of expression of the cloned gene, leaky expression without inducer, dependence of expression level on inducer concentration and cell population homogeneity) were found by determination of expression level of the model gfpuv gene by fluorescence intensity assay of the produced protein and by gfpuv-expressing C. glutamicum cell population analysis using flow cytometry. The vector pEC-XT99A was chosen for testing the bi-plasmid system for assignment of a sigma factor to the chosen promoter. Although the level of expression provided by pEC-XT99A was not high, the vector showed no leaky expression, expression from the vector was comparable for a wide range of IPTG concentrations and the cell population was homogenous concerning the gene expression. Using pEC-XT99A from which individual stress sig genes were expressed, the σD factor was clearly assigned to the up-to-now unknown Pcg0420 promoter. Another vector for isolation and purification of C. glutamicum proteins was used to express the C. glutamicum sigM gene and to...

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