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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.
31

Development of a computerized assessment tool for hand-arm function after stroke- test-retest reliability and convergent validity

Imran, Zoya 15 September 2016 (has links)
Many performance-based assessment tools are available to measure upper extremity function. Most define hand function by the time taken to complete a task. A new computer game-based hand-arm function evaluation (GHA) tool has been developed to quantify fine and gross object manipulations skills. Objective of this study was to evaluate the test-retest reliability and convergent validity of the GHA assessment tool. Thirty stroke clients with the mean age of 68.41 years were recruited. Test-retest reliability was assessed by Intraclass correlation coefficient (ICCs) and t-test. Convergent validity between GHA and the Wolf Motor Function Test (WMFT) was determined using the Pearson’s correlation coefficient. Most of the GHA outcome measures had moderate to high ICC (0.5-0.9). With scant exceptions, low correlations were observed between GHA measures and WMFT score. The ICC values reflected the complexity of the tasks, more complex task showed lower ICCs values. / October 2016
32

CAMK-II: AN INTEGRAL PROTEIN IN CELL MIGRATION

McLeod, Jamie Josephine Avila 25 April 2013 (has links)
Coordinated inductive and morphogenetic processes of gastrulation establish the zebrafish body plan. Gastrulation includes massive cell rearrangements to generate the three germ layers and shape the embryonic body. Three modes of cell migration must occur during vertebrate gastrulation and include: epiboly, internalization of the presumptive mesendoderm and convergent extension (C&E). C&E movements narrow the germ layers mediolaterally (convergence) and elongate them anteroposteriorly (extension) to define the embryonic axis. The molecular mechanisms regulating coordinated cell migrations remain poorly understand and studying these has become of great interest to researchers. Understanding cell migration during development is highly relevant to a number of human physiological processes. Abnormal cell migration during early development can lead to congenital defects, with improper cell migration during adult life potentially leading to the invasion and metastasis of cancer. By studying cell migration events, in vivo, new insights are to be found to both the function and malfunction of key embryonic and postembryonic migratory events. The non-canonical Wnt pathway has been identified as an evolutionarily conserved signaling pathway, regulating C&E cell movements during vertebrate gastrulation. With the absence of the non-canonical Wnts (ncWnts), Wnt5 and Wnt11, during zebrafish development leading to a shorter and broader body axis with defects in elongation during segmentation resulting in undulation of the notochord. While it is clear ncWnts are necessary for C&E, many of the downstream effectors regulating these cell movements have not been defined. Previous research has shown that activation of ncWnt signaling through Wnt5 or Wnt11 results in an increase in intracellular Ca2+ during zebrafish gastrulation. To determine if the Ca2+/Calmodulin-dependent protein kinase, CaMK-II, is a potential downstream target of the Ca2+ increases during ncWnt activation, CaMK-II’s role in C&E was assessed. This study identifies camk2b1 and camk2g1 as being necessary for C&E movements, and outlines the phenotype of the overall embryo as well as individual cells of camk2b1 and camk2g1 morphants. The defects of CaMK-II morphants are specifically linked to alterations in C&E cell movements, while cell fate and proliferation are unaffected. An increase in CaMK-II activation during gastrulation produces similar C&E defects, demonstrating the specificity of CaMK-II’s activation in facilitating these highly coordinated cellular movements. We show that CaMK-II is working downstream Wnt 11 and in parallel to JNK signaling during gastrulation C&E. Overall, these data identify CaMK-II as a required component of C&E movements during zebrafish development, downstream ncWnt signaling, and altering cell migration through changes in cell shape
33

Nonabsolutely convergent integrals / Nonabsolutely convergent integrals

Kuncová, Kristýna January 2011 (has links)
Title: Nonabsolutely convergent integrals Author: Kristýna Kuncová Department: Department of Mathematical Analysis Supervisor: Prof. RNDr. Jan Malý, DrSc., Department of Mathematical Analysis Abstract: Our aim is to introduce an integral on a measure metric space, which will be nonabsolutely convergent but including the Lebesgue integral. We start with spaces of continuous and Lipschitz functions, spaces of Radon measures and their dual and predual spaces. We build up the so-called uniformly controlled integral (UC-integral) of a function with respect to a distribution. Then we investigate the relationship between the UC-integral with respect to a measure and the Lebesgue integral. Then we introduce another kind of integral, called UCN-integral, based on neglecting of small sets with respect to a Hausdorff measure. Hereafter, we focus on the concept of n-dimensional metric currents. We build the UC-integral with respect to a current and then we proceed to a very general version of Gauss-Green Theorem, which includes the Stokes Theorem on manifolds as a special case. Keywords: Nonabsolutely convergent integrals, Multidimensional integrals, Gauss-Green Theorem 1
34

Associações ecológicas e evolutivas da forma da cabeça em lagartos serpentiformes (Squamata) / Ecological and evolutionary head shape associations in serpentiform lizards (Squamata)

Anelli, Vinicius 09 April 2019 (has links)
Convergências são frequentes na evolução da diversidade dos seres vivos. Padrões fenotípicos parecidos originados a partir de processos evolutivos independentes são interpretados como evidência da força da seleção natural na diversificação da vida. Corpos alongados e com apêndices locomotores reduzidos (i.e. serpentiformes) são frequentes e evoluíram em múltiplas linhagens de vertebrados. Ao menos 25 origens independentes do fenótipo serpentiforme são reconhecidas em Squamata, frequentemente associadas ao hábito fossorial. Explicações para essa frequente associação residem nas predições energéticas e biomecânicas envolvidas com o deslocamento por enterramento. A cabeça possui papel funcional relevante envolvido com a perfuração do substrato durante o deslocamento fossorial. Associação evolutiva entre a forma da cabeça e a fossorialidade foi descrita para a família de lagartos Gymnophthalmidae, mas generalizada para as duas linhagens serpentiformes independentes do grupo. No presente trabalho, morfometria geométrica de contorno foi implementada para testar a hipótese de que a forma da cabeça varia entre os representantes fossoriais de lagartos gimnoftalmídeos. Verificou-se que variações morfológicas são dependentes do tipo de substrato de enterramento, com espécies fossoriais que ocupam substratos arenosos apresentando cabeças mais pontiagudas e menores, diferindo significativamente de espécies que se deslocam em meio ao folhiço, com formatos mais arredondadas. O presente estudo também testou associações entre diferentes regimes de seleção e a evolução de fenótipos serpentiformes a partir de uma base de dados morfológicos e ecológicos abrangendo 198 espécies de todas as grandes linhagens de lagartos viventes. Os resultados indicam que a forma da cabeça evoluiu em associação ao hábito locomotor e ao microhabitat, com espécies fossoriais apresentando ótimos adaptativos distintos envolvidos com o tipo de solo no qual o enterramento ocorre, explicados pelas diferentes demandas seletivas impostas por distintos substratos. Os avanços detalhados neste trabalho contribuem para esclarecer como padrões convergentes evoluíram nos répteis escamados, revelando significativa diversidade quanto à forma da cabeça associada ao uso do microhabitat em espécies fossoriais / Convergence is ubiquitous to the striking diversity of life. Similar phenotypes originated by independent evolutionary processes are interpreted as evidence for the strength of natural selection. Elongated limb-reduced bodies are frequent and evolved multiple times among vertebrates. At least twenty-five independent origins of snakelike phenotypes are recognized for Squamata, frequently associated to fossorial environments. Explanations for the frequent occurrence of elongated limbless forms in association to fossoriality reside in the functional and biomechanical predictions of such phenotype for burrowing. Head plays an important functional role in excavating the soil during head-first burrowing. Evolutionary associations between skull shape and fossoriality were described for Gymnophthalmidae lizards, although patterns were generalized for both independent origins of snakelike, fossorial forms in the family. In our study, outline geometric morphometric was implemented in order to test the hypothesis that head shape varies among fossorial gymnophthalmids. Our findings indicate that such variations are substrate-dependent in Gymnophthalmidae, as sandswimmer gymnophthalmids exhibit smaller, narrow-snouted heads, whereas leaf-litter dwellers differ in head shape patterns, with rounded heads. Our study also tested associations between distinct selective regimes and the evolution of snakelike phenotypes for lizards in general, as from an ecomorphological database comprising 198 species from all continents, representing all the major lizard lineages recognized. Results indicate that skull shape evolved in association to locomotion and to microhabitat, as fossorial species evolve towards distinct adaptive optima according to the burrowing substrate, since head is in direct contact with soil during locomotion and subject to distinct selective demands imposed by substrate specificities. The advances described in our study contribute to clarify how convergent patterns evolve among squamates, unveiling considerable diversity in head shape associated to microhabitat use in fossorial species
35

Proposta de uma arquitetura para o fornecimento de serviços móveis em redes convergentes heterogêneas com foco no usuário. / Proposal of architecture to supply mobile services at heterogeneous convergent network with focus on user.

Sakurai, Cledson Akio 31 March 2010 (has links)
Devido às redes convergentes, os usuários dos produtos de telecomunicações passaram a ter disponíveis serviços mais completos, desde a simples possibilidade de escolha da tecnologia de acesso para os serviços de dados, passando por serviços com conteúdo multimídia com qualidade assegurada e usando diferentes tecnologias de acesso, entretanto este novo cenário traz consigo uma complexidade tecnológica que dificulta a escolha do produto mais apropriado a cada necessidade do usuário. O advento das redes convergentes permite que o usuário possa ter serviços que atendam as suas necessidades em termos de funcionalidade, mobilidade e qualidade, mas a escolha do produto mais adequado de cada provedora de telecomunicações não é fácil para a maioria dos usuários, portanto a presente tese propõe um modelo de negócios para o segmento de telecomunicações que, ao invés de prover produtos, passa a fornecer serviços adequados a cada necessidade do usuário, atendendo sua necessidade em termos de qualidade de serviços, permitindo melhor compreensão dos parâmetros da qualidade fornecida. O modelo de negócios proposto nesta tese cria quatro provedoras, sendo que três provedoras fornecem produtos de conteúdo (Provedora de Conteúdo), infraestrutura (Provedora de Infraestrutura) e acesso (Provedora de acesso), e uma provedora, chamada Provedora de Serviços, que fornecerá o serviço ao usuário final, que é formado pelos produtos das provedoras citadas. Além disso, a provedora de serviços ficará responsável pelo fornecimento do serviço que atenda as necessidades de mobilidade e qualidade de serviços adequada a cada usuário final. Esta tese, também, apresenta uma proposta de adequação do modelo e-TOM (Enhanced Telecom Operations Map) proposto pelo TMF (TeleManagement Forum) em atendimento ao novo modelo de negócios proposto, e uma arquitetura aberta baseada no NESSI (Networked European Software & Services Initiative) da comunidade européia que viabiliza o modelo de negócios proposto. O estudo de caso apresenta a implementação de um sistema de gestão de força de trabalho para empresas de telecomunicações baseado na arquitetura proposta que atende ao modelo de negócios proposto, essa implementação está sendo parcialmente financiada pela FINEP (Financiadora de Estudos e Projetos) através do projeto SGSCENU-SISTEMA GESTOR DE SERVIÇOS CENTRADO NO USUÁRIO, convênio 01.08.0519.00, iniciado em março de 2009 com término previsto em março de 2011. O modelo de negócios proposto apresenta uma quebra de paradigma para o mercado de telecomunicações que é o foco no usuário final, e não nos produtos. No cenário proposto o usuário final seleciona o serviço que melhor atende à sua necessidade com a qualidade de serviços desejada e as provedoras de serviços fornecem serviços que melhor atendam a necessidade do usuário final, sem no entanto realizar grandes investimentos, pois pode utilizar os produtos fornecidos pelas demais provedoras. O modelo de negócios proposto necessita uma adequação nos processos de negócios, pois as provedoras passam a ser complementares entre si e compartilham produtos nas mais diversas situações. E para atender a esta característica é necessário uma arquitetura que integre os sistemas das provedoras de forma transparente, permitindo que a provedora de serviços forneça o serviço de acordo com a qualidade de serviço contratada pelo usuário final. / Due to convergent networks, telecommunications products users available now have more complete services, from simple choice of access technology to data services, to new services with multimedia content with assured quality and used different access technologies, however this new scenario brings with it a technological complexity makes it difficult to choose the product that suits every need of user. The advent of convergent networks allows the user may have services that meet their needs in terms of unctionality, mobility and quality, but choosing the most suitable product for every telecommunications provider is not easy for most users, so this thesis proposes a business model for the telecommunications segment that instead of providing products is to provide adequate services to meet every need of the user, given their need for quality services, allowing better understanding of the quality parameters supplied. The business model proposed in this thesis creates four providers being three providers provide content products (Content Provider), infrastructure (Infrastructure Provider) and access (Internet Service Provider) and a provider, called the Service Provider will provide the service to the end user, which is formed by the products of listed providers. In addition, the service provider will be responsible for providing service that meets the needs of mobility and quality of services tailored to each end user. This thesis also presents a proposal to adapt the model e-TOM (Enhanced Telecom Operations Map) proposed by the TeleManagement Forum (TMF) in response to the new business model proposed, and an open architecture based on NESSI (Networked European Software & Services Initiative) of the European community that enables the business model proposed. The study case describes the implementation of a management system of labor for telecommunications companies based on the proposed architecture that addresses the business proposed model, this implementation is being partially financed by FINEP (Financier of Studies and Projects) project SGSCENU-SYSTEM MANAGER SERVICES focused on the user agreement 01.08.0519.00, started in March 2009 with completion expected in March 2011. The proposed business model presents a paradigm shift for the telecommunications market that is the focus on the end user, and not the products. In the proposed scenario the end user selects the service that best fits your need with the quality of services desired, and service providers to provide services that best meet the need of the end user, without making major investments because you can use the products supplied by other providers. The proposed business model needs an appropriate business processes, because the providers become complementary to each other and share products in a variety of situations. And to accommodate this feature you need an architecture that integrates the systems of providers in a transparent manner, allowing the service provider provides the service according to the quality of service contracted by the end user.
36

Are changes at ARP and KNOX genes responsible for the evolution of leaf form in Begonia section Gireoudia?

Umbreen, Saima January 2011 (has links)
Leaf primordia initiation takes place at the flanks of SAM and then passes through common developmental stages. Very different final leaf shapes and sizes result from varying the timing and further patterning events within these developmental stages. Similar final leaf shapes may also result from very distinct early events. Begonia section Gireoudia is a recently radiated group of species with highly divergent leaf forms. I have used a classical genetic approach and candidate gene approach to explain the evolution of leaf form in this genus. These results suggest that convergent evolution of peltate leaves may be through changes at different loci. Key developmental regulators KNOX and ARP genes are reported to be involved in the evolution of leaf form in different species. I have shown that in at least one species ARP is linked to the evolution of peltate leaf form. In a second species there is no link between STM-like KNOX genes and leaf dissection. Estimates of the rate of evolution of ARP CDS showed that different domains of the genes are under different selection pressures. Myb domain2 of ARP genes is under positive selection and variable between two copies of ARP genes in Begonia. Results of complementation tests with Begonia ARP genes in Arabidopsis show that ARPs from Begonia are functionally equivalent to Arabidopsis AS1 genes and one of the two ARP genes in Begonia may be a dominant negative. Expression analysis based on insitu hybridization in compound, peltate and simple leaved Begonias is described. There is no variation in expression patterns between peltate, non peltate or compound leaved Begonia species for BARP1 and KNB1 genes.
37

Proposta de uma arquitetura para o fornecimento de serviços móveis em redes convergentes heterogêneas com foco no usuário. / Proposal of architecture to supply mobile services at heterogeneous convergent network with focus on user.

Cledson Akio Sakurai 31 March 2010 (has links)
Devido às redes convergentes, os usuários dos produtos de telecomunicações passaram a ter disponíveis serviços mais completos, desde a simples possibilidade de escolha da tecnologia de acesso para os serviços de dados, passando por serviços com conteúdo multimídia com qualidade assegurada e usando diferentes tecnologias de acesso, entretanto este novo cenário traz consigo uma complexidade tecnológica que dificulta a escolha do produto mais apropriado a cada necessidade do usuário. O advento das redes convergentes permite que o usuário possa ter serviços que atendam as suas necessidades em termos de funcionalidade, mobilidade e qualidade, mas a escolha do produto mais adequado de cada provedora de telecomunicações não é fácil para a maioria dos usuários, portanto a presente tese propõe um modelo de negócios para o segmento de telecomunicações que, ao invés de prover produtos, passa a fornecer serviços adequados a cada necessidade do usuário, atendendo sua necessidade em termos de qualidade de serviços, permitindo melhor compreensão dos parâmetros da qualidade fornecida. O modelo de negócios proposto nesta tese cria quatro provedoras, sendo que três provedoras fornecem produtos de conteúdo (Provedora de Conteúdo), infraestrutura (Provedora de Infraestrutura) e acesso (Provedora de acesso), e uma provedora, chamada Provedora de Serviços, que fornecerá o serviço ao usuário final, que é formado pelos produtos das provedoras citadas. Além disso, a provedora de serviços ficará responsável pelo fornecimento do serviço que atenda as necessidades de mobilidade e qualidade de serviços adequada a cada usuário final. Esta tese, também, apresenta uma proposta de adequação do modelo e-TOM (Enhanced Telecom Operations Map) proposto pelo TMF (TeleManagement Forum) em atendimento ao novo modelo de negócios proposto, e uma arquitetura aberta baseada no NESSI (Networked European Software & Services Initiative) da comunidade européia que viabiliza o modelo de negócios proposto. O estudo de caso apresenta a implementação de um sistema de gestão de força de trabalho para empresas de telecomunicações baseado na arquitetura proposta que atende ao modelo de negócios proposto, essa implementação está sendo parcialmente financiada pela FINEP (Financiadora de Estudos e Projetos) através do projeto SGSCENU-SISTEMA GESTOR DE SERVIÇOS CENTRADO NO USUÁRIO, convênio 01.08.0519.00, iniciado em março de 2009 com término previsto em março de 2011. O modelo de negócios proposto apresenta uma quebra de paradigma para o mercado de telecomunicações que é o foco no usuário final, e não nos produtos. No cenário proposto o usuário final seleciona o serviço que melhor atende à sua necessidade com a qualidade de serviços desejada e as provedoras de serviços fornecem serviços que melhor atendam a necessidade do usuário final, sem no entanto realizar grandes investimentos, pois pode utilizar os produtos fornecidos pelas demais provedoras. O modelo de negócios proposto necessita uma adequação nos processos de negócios, pois as provedoras passam a ser complementares entre si e compartilham produtos nas mais diversas situações. E para atender a esta característica é necessário uma arquitetura que integre os sistemas das provedoras de forma transparente, permitindo que a provedora de serviços forneça o serviço de acordo com a qualidade de serviço contratada pelo usuário final. / Due to convergent networks, telecommunications products users available now have more complete services, from simple choice of access technology to data services, to new services with multimedia content with assured quality and used different access technologies, however this new scenario brings with it a technological complexity makes it difficult to choose the product that suits every need of user. The advent of convergent networks allows the user may have services that meet their needs in terms of unctionality, mobility and quality, but choosing the most suitable product for every telecommunications provider is not easy for most users, so this thesis proposes a business model for the telecommunications segment that instead of providing products is to provide adequate services to meet every need of the user, given their need for quality services, allowing better understanding of the quality parameters supplied. The business model proposed in this thesis creates four providers being three providers provide content products (Content Provider), infrastructure (Infrastructure Provider) and access (Internet Service Provider) and a provider, called the Service Provider will provide the service to the end user, which is formed by the products of listed providers. In addition, the service provider will be responsible for providing service that meets the needs of mobility and quality of services tailored to each end user. This thesis also presents a proposal to adapt the model e-TOM (Enhanced Telecom Operations Map) proposed by the TeleManagement Forum (TMF) in response to the new business model proposed, and an open architecture based on NESSI (Networked European Software & Services Initiative) of the European community that enables the business model proposed. The study case describes the implementation of a management system of labor for telecommunications companies based on the proposed architecture that addresses the business proposed model, this implementation is being partially financed by FINEP (Financier of Studies and Projects) project SGSCENU-SYSTEM MANAGER SERVICES focused on the user agreement 01.08.0519.00, started in March 2009 with completion expected in March 2011. The proposed business model presents a paradigm shift for the telecommunications market that is the focus on the end user, and not the products. In the proposed scenario the end user selects the service that best fits your need with the quality of services desired, and service providers to provide services that best meet the need of the end user, without making major investments because you can use the products supplied by other providers. The proposed business model needs an appropriate business processes, because the providers become complementary to each other and share products in a variety of situations. And to accommodate this feature you need an architecture that integrates the systems of providers in a transparent manner, allowing the service provider provides the service according to the quality of service contracted by the end user.
38

Evolução convergente da protease FtsH5 de Arabidopsis thaliana e seu regulador negativo putativo FIP (FtsH5 interacting protein) / Convergent evolution of Arabidopsis thaliana FtsH5 protease and its putative negative regulator FIP (FtsH5 interacting protein)

Silva, Marcos Araújo Castro e 02 March 2015 (has links)
As metaloproteases AAA/FtsH são componentes chave do controle da qualidade das proteínas inseridas nas membranas de mitocôndrias e cloroplastos. Em Arabidopsis thaliana, as proteases FtsH presentes nas membranas dos tilacóides formam um complexo heterohexamérico composto pelas subunidades FtsH1/FtsH5 (tipo A) e FtsH2/FtsH8 (tipo B). Este complexo está envolvido na reciclagem de proteínas foto-danificadas, especialmente da proteína D1, centro de reação do PSII. Algumas linhas de evidências indicam ainda que existe um limiar de concentração das proteases FtsH, necessário para a correta formação e desenvolvimento dos cloroplastos. Apesar da extensiva caracterização genética e molecular das proteases FtsH, o mecanismo regulatório do complexo FtsH dos cloroplastos não foi totalmente elucidado até o momento, contudo existem evidências de que a sua ativação pode estar relacionada a alta incidência luminosa e a outras condições de estresse. A presença de fatores proteicos auxiliares, foi testada como hipótese alternativa por nosso grupo, através do uso da protease FtsH5 como isca em um ensaio de duplo híbrido de leveduras. Este ensaio identificou uma proteína interagente putativa, nomeada FIP (FtsH5 Interacting Protein), a qual comprovadamente interage com FtsH5 e está localizada nas membranas dos tilacóides. De modo a investigar o papel regulatório putativo de FIP sobre a atividade do complexo FtsH, nós analisamos os padrões de expressão em uma ampla gama de condições de estresse a partir de dados públicos de microarranjos de DNA. Os perfis de expressão indicam que FIP pode ser um regulador negativo da atividade do complexo. Os resultados também sugerem que o complexo pode estar envolvido na resposta do cloroplasto a diferentes tipos de condições de estresse. O estudo da história evolutiva das proteínas interagentes FtsH5 e FIP evidenciou que as sequências homólogas a FIP são encontradas exclusivamente em musgos e plantas superiores, sugerindo assim que a origem de FIP pode estar relacionada a colonização terrestre. Todos os genes codificantes das proteases FtsH do complexo foram usados como \"query\" na busca por sequências homólogas, permitindo a classificação das proteases FtsH nos tipos A e B por inferência filogenética Bayesiana. Análises filogenéticas Bayesianas também foram feitas para FIP e as proteases FtsH tipos A e B, independentemente. A análise Mirrortree suportou a existência de coevolução entre FIP e as proteases FtsH tipo A. Por outro lado, nenhuma correlação foi encontrada entre FIP e as proteases FtsH tipo B, o que corrobora nossas observações experimentais anteriores. Além disso, o agrupamento portador de homólogos FIP pôde ser recuperado em uma filogenia mais completa das proteases FtsH do tipo A. Análises subsequentes mostraram que ambas as proteínas interagentes estão extensivamente sobre seleção negativa e que proteases FtsH tipo A são bastante conservadas, principalmente nos seus domínios internos. / Eukaryotic AAA/FtsH metalloproteases display a key role in the protein quality control of membrane-inserted proteins in mitochondria and chloroplasts. In Arabidopsis thaliana, chloroplast thylakoidal membranes FtsH proteases form a heterohexameric complex made by FtsH1/FtsH5 (type A) and FtsH2/FtsH8 (type B) subunits. This complex is involved in protein turnover of photo-damaged proteins, in particular the D1 protein at the PSII reaction center. Several lines of evidence also indicate that a FtsH threshold level is necessary for the proper formation and development of chloroplasts. Despite extensive genetic and molecular characterization of the FtsH proteases, the regulatory mechanism of the FtsH complex in chloroplasts has not yet been fully elucidated, however, there are evidences that its activation might be related to high light incidence and other stress conditions. The presence of auxiliary protein factors, as an alternative hypothesis, was tested by our group, through the use of the protease FtsH5 as bait in a yeast two-hybrid assay. This essay identified a putative interacting protein named FIP (FtsH5 Interacting Protein), which has been proved to interact with FtsH5 and be located at the thylakoid membranes. In order to investigate a putative regulatory role of FIP on FtsH complex activity, we analyzed gene expression patterns in a wide range of stress conditions from public DNA microarray data. The expression profiles indicate that FIP could be a negative regulator of the FtsH complex activity. The results also suggest that the complex may be involved in the chloroplast response to different types of stress conditions. In order to shed some light on the evolutionary history of FtsH5 and FIP interacting proteins, we have shown that FIP\'s homologous sequences were exclusively found in mosses and higher plants, suggesting that FIP origin might be related to the plant terrestrial colonization. All Arabidopsis FtsH complex-encoding genes were used as \"query\" sequences in search for homologous sequences, allowing us to classify the FtsH proteases in type A and B by Bayesian phylogenetic inference. Bayesian phylogenetic analyses were also run for FIP and FtsH types A and B proteases, independently. Mirrortree analysis supported coevolution between FIP and type A FtsH proteases. On the other hand, no correlation was found between FIP and type B FtsH homologues, which support our previous experimental observations. In addition, the FIP bearing cluster could be recovered in a more complete type A FtsH phylogeny. Subsequent analyzes have shown that both interacting proteins are extensively under negative selection and that type A FtsH are very conserved, mainly in its inner domains.
39

OPTIMIZATION OF NOZZLE SETTINGS FOR A FIGHTER AIRCRAFT

Stenebrant, Alexander, Al-Mosawi, Nor January 2019 (has links)
Most fighters use the convergent-divergent nozzle configuration to accelerate into the supersonic realm. This nozzle configuration greatly increases the thrust potential of the aircraft compared to the simpler convergent nozzle. The nozzle design is not only crucial for thrust, but also for the drag since the afterbody drag can be as high as 15% of the total. Engine manufacturers optimize the engine and the nozzle configurations for the uninstalled conditions, but these may not be optimal when the engine is installed in the aircraft. The purpose of this study is to develop a methodology to optimize axisymmetric nozzle settings in order to maximize the net thrust. This was accomplished by combining both simulations of thrust and drag. The thrust model was created in an engine performance tool, called EVA, with the installed engine performance of a low bypass turbofan jet engine at maximum afterburner power setting. The drag model was created with CFD, where the mesh was built in ICEM Mesh and the simulations were run with the CFD solver M-Edge. Five Mach numbers in the range from 0.6 to 1.6 were simulated at an altitude of 12 km. The results showed that the afterbody drag generally decreased when increasing jet pressure ratio at both subsonic and supersonic velocities. At subsonic conditions, increasing nozzle area ratio for underexpanded nozzles would decrease the drag. Increasing nozzle area ratio for fully expanded or overexpanded nozzles would instead increase the drag to an intermediate point from where it would decrease. At supersonic condition, increasing nozzle area ratio would generally cause reduction in drag for all cases. The optimization showed that a net thrust increase of 0.02% to 0.09% could be gained for subsonic conditions while the supersonic optimization had negligible gain in thrust.
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Validation of the Scores of the Instructional Pedagogical and Instructional Student Engagement Components of Fidelity of Implementation

Naoom, Sandra F. 28 August 2014 (has links)
Students cannot benefit from what they do not experience. Multiple reasons exist for why an intervention may not be delivered as it was designed. In this era of educational accountability and limited dollars to go around, understanding how an intervention is delivered in the classroom is key to understanding program outcomes. In order to assess whether a program has been implemented as intended, an assessment of fidelity is needed. However assessing fidelity is complex given varying conceptual interpretations, which then fosters inconsistent application of methods to measure the construct. Additionally the methods for validating fidelity measures are still unclear. The current study evaluated the reliability and validity of the student Instructional Pedagogical (10 items) and Instructional Student Engagement (15 items) scores for use in assessing teachers' fidelity of implementation on the participant responsiveness component of fidelity. The sample consisted of over 5,000 responses from students and 242 teachers in Mathematics and Science across three school districts and 41 schools to an online fidelity of implementation questionnaire. Given that students were nested within teachers, the data structure was multilevel, which warranted that the psychometric analyses be conducted using a multilevel framework. Instructional Pedagogy is represented by 10 items that measure three factors. Multilevel confirmatory factor analysis was used to test a two-level model that had three factors at the student-level and three factors at the teacher-level. Instructional Student Engagement is represented by 15 items that measure four factors. Multilevel confirmatory factor analysis was used to test a two-level model that had four factors at the student-level and four factors at the teacher-level. The psychometric results of the student questionnaire assessing the student engagement components of fidelity were mixed. Support for the factorial validity of the multilevel student models was mixed, with model fit indicating that some of the measured variables did not load strongly on their respective factors and some of the factors lacked discriminant validity. Lastly, the correlations between students' and teachers' scores for both the observed and latent variables (ranging from -.15 to .72 in math; -.07 to .41 in science) displayed limited convergent validity.

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