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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.
191

Contribuições ao estudo da gestão do conhecimento e da colaboração universidade-empresa-governo: proposição conceitual e estudo de casos em Institutos Nacionais de Ciência e Tecnologia no Brasil / A conceptual proposition and case studies conducted at Brazilian National Institutes of Science and Technology for the analysis of knowledge management and university-industry-government collaboration

Suzana Xavier Ribeiro 13 July 2017 (has links)
O propósito desta tese é investigar como a gestão do conhecimento e a colaboração universidade-empresa-governo incluindo as três hélices se relacionam influenciando o desempenho das organizações. Como principal contribuição, pretende-se propor um modelo analítico que relaciona as teorias da Gestão do Conhecimento e da Tripla Hélice, modelo mais referenciado para aprofundar esse tipo de cooperação, e as dimensões propostas (que são a estrutural, a relacional, a cognitiva e o contexto), considerando as particularidades do contexto brasileiro. No ambiente competitivo contemporâneo, a capacidade de as organizações criarem e utilizarem o conhecimento torna-se cada vez mais fundamental para a busca da vantagem competitiva sustentável, o que leva inclusive à busca de novas formas de arranjos interorganizacionais. A escolha do tema se justifica pela escassez de pesquisas empíricas que relacionem os tópicos de gestão do conhecimento e de colaboração universidade-empresa-governo de forma integrada com foco no contexto brasileiro. Os representantes desse tipo de colaboração selecionados para compor o estudo são Institutos Nacionais de Ciência e Tecnologia (INCTs). Como técnica qualitativa de análise de dados foi utilizada a análise de conteúdo categorial. Os principais resultados mostram que a estrutura organizacional (estrutural) influencia tanto o relacionamento entre os integrantes (relacional) quanto o fluxo de conhecimento (cognitiva), bem como os elementos relacionais (cultura colaborativa, confiança e liderança) facilitam o compartilhamento de conhecimento. Além disso, o contexto afeta essas três outras dimensões. Como principais barreiras no processo de transferência de conhecimento são identificadas as diferenças culturais, a burocracia e a realidade socioeconômica, e como facilitadores a presença de parques tecnológicos e incubadoras, a proximidade geográfica entre universidade e empresa e os incentivos governamentais. / This thesis focuses on an investigation into the way knowledge management and university-industry-government collaboration influence the performance of organizations. As the main contribution, an analytical model that relates the theories of Knowledge Management and the Triple Helix, the most referenced model for such cooperation, and the structural, relational, cognitive dimensions, as well as the context is proposed. The model takes into consideration the particularities of the Brazilian context. In todays competitive environment, the ability of organizations to create and use their knowledge has become fundamental for their pursuit of sustainable competitive advantages and new forms of organizational arrangements. The choice of the topic is justified by the scarcity of studies on the identification and analyses of the main aspects of this form of collaboration in an integrated way and focused on the Brazilian context. A categorical content analysis was used as a qualitative technique applied for a multiple case study of National Institutes of Science and Technology (INCTs). The results show both context and organizational structure (structural dimension) influence the relationship between members (relational dimension) and flow of knowledge (cognitive dimension) and the relational elements (collaborative culture, trust and leadership) facilitate knowledge sharing. Cultural differences, bureaucracy and socioeconomic reality were identified as the main barriers in the process of knowledge transfer, whereas facilitators included presence of science parks and incubators, geographical proximity between university and business and government incentives.
192

Determinantes dos depósitos de patentes em ciências da vida e da saúde nas unversidades federais mineiras: uma análise de dados em painel para o período 1995-2016 / Determinants of patent deposits in life sciences and health in the federal university of Minas Gerais: a panel data analysis for the period 1995-2016

Cóser Sobrinho, Inaiara 11 July 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-08-24T19:24:23Z No. of bitstreams: 1 inaiaracosersobrinho.pdf: 1426545 bytes, checksum: 55114c9f9b21705eba3b5315ee786256 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-25T12:04:45Z (GMT) No. of bitstreams: 1 inaiaracosersobrinho.pdf: 1426545 bytes, checksum: 55114c9f9b21705eba3b5315ee786256 (MD5) / Made available in DSpace on 2017-08-25T12:04:45Z (GMT). No. of bitstreams: 1 inaiaracosersobrinho.pdf: 1426545 bytes, checksum: 55114c9f9b21705eba3b5315ee786256 (MD5) Previous issue date: 2017-07-11 / Devido à natureza evolucionária do sistema econômico, as mudanças de paradigmas induzem aos padrões de crescimento chamados de ondas longas. Essas mudanças, que ocorrem em média a cada 50 anos, são ocasionadas pela inserção de inovações disruptivas que revolucionam incessantemente a estrutura econômica, destruindo o antigo e criando novos elementos, não apenas a nível econômico, mas institucional, organizacional e social. Na década de 90, com o desenvolvimento da microeletrônica e das tecnologias de comunicações, emergiu o paradigma da tecnologia da informação, caracterizado pela intensidade de informação que, transformada em conhecimento e inovação, desempenha um papel crucial para desenvolvimento. Entretanto, para que isso ocorra, é necessário que os países construam arranjos institucionais apropriados. Com isso, surge o modelo de sistemas de inovação da Tríplice Hélice. Este modelo compreende a inovação e o progresso técnico, numa Economia do Conhecimento, como o resultado de um conjunto complexo de relações entre universidade-empresa-governo, atores diretamente envolvidos na produção, distribuição e aplicação do conhecimento. Neste contexto, o presente estudo teve o objetivo de identificar o impacto da produção de conhecimento e das políticas públicas para a produção de depósitos de patentes dos pesquisadores pertencentes ao domínio científico Ciências da Vida e da Saúde, das universidades federais mineiras. A análise considerou o período de 1995 a 2016. Para isso, foram utilizadas as técnicas de análise exploratória dos dados e de análise em painel. Os resultados mostraram que fatores educacionais (orientações em pós-graduação), econômicos (produtos tecnológicos e prestação de serviços tecnológicos) e políticos (arcabouço legal, recursos financeiros e políticas de estímulo) impactaram a produção de depósitos de patentes dos pesquisadores pertencentes ao domínio científico Ciências da Vida e da Saúde das universidades federais mineiras. A experiência acadêmica e o conhecimento científico, principal insumo para gerar inovação, não foram determinantes para a produção de depósitos de patente. Já os fatores políticos apresentaram um forte impacto, tanto na produção de conhecimento quanto nos depósitos de patente. Isso demonstra os esforços do Governo para tentar diminuir o hiato tecnológico. / Due to the evolutionary nature of the economic system, paradigm shifts induce the growth patterns called long waves. These changes, which occur on average every 50 years, are brought about by the insertion of disruptive innovations that unceasingly revolutionize the economic structure, destroying the old and creating new elements, not only at an economic but institutional, organizational and social level. In the 1990s, with the development of microelectronics and communications technologies, the paradigm of information technology emerged, characterized by the intensity of information that, transformed into knowledge and innovation, plays a crucial role in development. However, to trigger this process, countries need to build appropriate institutional arrangements. Appears, with it, the model of systems of innovation of the Triple Helix. This model comprises innovation and technical progress in a Knowledge Economy as the result of a complex set of relations between university-business-government. Being these the actors that are directly involved in the production, distribution, and application of knowledge. In this context, the present study aimed to identify the impact of the production of knowledge and public policies to produce patent deposits of researchers from the scientific field of Life Sciences and Health, from the federal universities of Minas Gerais. The analysis considered the period from 1995 to 2016. For this, the techniques of exploratory data analysis and panel data analysis were used. The results showed that educational factors (post-graduation orientations), economic (technological products and technological services provision) and political (legal framework, financial resources, and stimulus policies) impact the production of patent deposits of researchers belonging to the scientific domain Life Sciences and Health of the federal universities of Minas Gerais. Academic experience and scientific knowledge, the main input to generate innovation, were not decisive to produce patent deposits. On the other hand, the political factors had a strong impact, both in the production of knowledge and in patent deposits. This demonstrates the efforts of the Government to try to reduce the technology gap.
193

Sustentação de corrente utilizando campos magnéticos viajantes helicoidais / Helical traveling wave current drive

Duarte, Vinícius Njaim, 1988- 19 August 2018 (has links)
Orientadores: Roberto Antonio Clemente, Munemasa Machida / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-19T20:53:40Z (GMT). No. of bitstreams: 1 Duarte_ViniciusNjaim_M.pdf: 5509797 bytes, checksum: 163bd7750aa0326f7bf0d0b521dc88f0 (MD5) Previous issue date: 2012 / Resumo: Entre os diferentes métodos alternativos à indução, para sustentação e/ou geração de corrente em plasmas confinados magneticamente, com o objetivo de se obter o funcionamento contínuo de um possível reator de fusão, foi estudado aquele associado a campos magnéticos viajantes produzidos por bobinas helicoidais alimentadas por correntes de radiofrequência defasadas (double helix current drive). O método permite compensar as perdas de caráter resistivo em configurações toroidais de plasma, como os pinches de campo reverso (reversed field pinches - RFP). O problema pode ser reduzido ao estudo dos estados estacionários de uma coluna de plasma sujeita a campos de radiofrequência produzidos por bobinas helicoidais externas. Desprezando efeitos de gradientes de densidade e temperatura, o modelo é regido por um sistema de equações diferenciais ordinárias de segunda ordem não lineares acopladas, reguladas por quatro parâmetros adimensionais de interesse físico, que foram resolvidas numericamente usando o programa Mathematica. Estudou-se a eficiência do método em relação às aplicações em RFP, para os quais o campo magnético longitudinal apresenta uma inversão no interior da coluna de plasma. Isso implicou considerar regiões ainda não bem exploradas para os parâmetros de interesse. Os resultados numéricos são apresentados para configurações de campos magnéticos com simetria dipolar e quadrupolar / Abstract: Among the different methods, alternative to induction, to drive current in magnetically confined plasmas, with aim to obtain a continuous operation of a possible fusion reactor, we have studied the one associated to traveling magnetic field produced by helicoidal coils carrying out of phase radiofrequency currents (double helix current drive). The method allows compensating resistive losses in toroidal plasma configurations, like reversed field pinches. The problem may be reduced to the study of stationary states for a plasma column subjected to radiofrequency fields produced by external helicoidal coils. Neglecting density and temperature gradients, the model is governed by a system of coupled nonlinear second order ordinary differential equations, which depend on four dimensionless parameters of physical interest and can be solved numerically using the software Mathematica. We studied the efficiency of the method with respect to applications in reversed field pinches, for which the longitudinal steady magnetic field shows an inversion inside the plasma column. This implied considering not yet well explored regions of the parameters of interest. Numerical results are presented for magnetic field configurations of dipolar and quadrupolar simmetries / Mestrado / Física / Mestre em Física
194

Nouveaux tripodes tris-A,C,E-alpha-Cyclodextrine et leurs complexes Métallo-supramoléculaires / New tris-A,C,E-alpha-cyclodextrin tripod and their metallo-supramolecular complexes

Poisson, Guillaume 16 October 2012 (has links)
Ce travail s'articule autour de deux grandes parties : i- la synthèse de nouveaux tripodes tris-A,C,E-alpha-cyclodextrine, et l'étude de leurs complexes de coordination avec les métaux. La fonctionnalisation des bis-hétérocycles est une étape importante dans la préparation de ces tripodes moléculaires. En conséquence, la mise au point d'une nouvelle famille de réactifs, les tétrahalogeno-diarylglycoluriles, a permis une halogénation radicalaire sélective des systèmes hétéro-aromatiques pi-déficients non réactifs et impliqués dans la construction des podants cyclodextriniques. La sélectivité et le mécanisme de la réaction ont pu être expliqués en partie par la formation d'un complexe supramoléculaire [réactif /substrat] et l'existence d'interactions halogène-halogène dans le solide; ii- la mise en évidence d'une haute spéciation des tripodes cyclodextrines vis-à-vis d'un certain nombre de métaux et la formation d'hélices métallo-supramoléculaires chirales induite par l'implantation en position 6,6' des unités hétérocycliques. La configuration absolue des hélicates formés est résolue dans quelques cas / This work is structured around two main parts: i- the synthesis of new tris-A,C,E-alpha-cyclodextrin tripods, and studies of their complexes with transition metals. The functionalization of bis-heterocycles is an important step in the preparation of tripods. Therefore, the development of a new family of reagents tetrahalo-diarylglycolurils allowed a selective radical halogenation of heteroaromatic pi-deficient systems, non-reactive and involved in the construction of podants cyclodextrinics. The selectivity and the mechanism of the reaction could be partially explained by the formation of a supramolecular complex [reagent / substrate] and the existence of halogen-halogen interactions in solid state; ii- the highlight of a high speciation tripods cyclodextrins towards a number of metals and formation of supramolecular chiral metallo-helices induced by anchoring in position 6,6' of heterocyclic units. The absolute configuration of helicates formed in some cases is resolved
195

The Influence of the Proximal Amide Hydrogen Bonds and the Proximal Helix Dipole on the Catalytic Activity of Chloroperoxidase

pardillo, armando d. 02 November 2015 (has links)
Chloroperoxidase (CPO) is a heme-thiolate protein with exceptional versatility and great potential as a biocatalyst. The CPO reactive species, Compound I ( Cpd I) is of particular interest, as well as the Cytochrome P450 (P450) -type monoxygenase catalytic activity, which has significant biotechnological potential. Proximal hydrogen bonding of the axial sulfur with the backbone amides (NH•••S) is a conserved feature of heme-thiolate enzymes. In CPO, the effect of NH•••S bonds is amplified by the dipole moment of the proximal helix. The role of the proximal region has been disputed as to whether it simply protects the axial sulfur, or whether it additionally influences catalysis via modulation of the push effect. The objective of the research presented herein is two-fold. First, the influence of the NH•••S bonds on Cpd I formation is determined by obtaining the reaction coordinate, starting from a peroxide bound heme, for two model systems (one with proximal residues providing NH•••S bonds and one without) and comparing the results. Secondly, the influence of the proximal region on the epoxidation of Cis-β-methylsterene is obtained. This is performed similarly to the first objective however, the reaction coordinate begins with a Cpd I-CBMS complex and the proximal contribution is extended to include the influence of the proximal helix dipole. Our findings show that the proximal region stabilizes Cpd 0 relative to all other minima and reduces the barrier for Cpd 0’s formation. The stability of protonated Compound 0 is reduced, favoring a hybrid homo-heterolytic relative to a classic heterolytic mechanism for O-O bond scission. Additionally, the proximal region significantly enhances CPO’s reactivity; the Cβ-O bond barrier is stabilized, while Cα-O-Cβ ring closure becomes barrierless. The stabilization of the reaction barrier correlates with increased electron density transfer to residues of the proximal pocket and involves a change in the electron transfer mechanism. These results can be traced to a reduction in the pKa of the heme-bound substrate and an increase in oxidation potential, a result of the proximal region reducing the “push effect”.
196

A Relationship Between the Strengths of Type N Cubic Mortar Specimens and In-Situ Mortar

Reynolds, Michael Scott 01 May 2019 (has links)
The compressive strength of mortar is typically determined using the American Societyfor Testing and Materials (ASTM) standard method using 2 inch cubes which are compressed tillfailure. There is however a disparity between the compressive strengths of mortar cubes, and insitumortar. This disparity is a result of the differences in thickness, aspect ratio, curingconditions, water content, and confinement between mortar cubes and mortar joints. While thesedifferences lead to mortar joints being stronger than mortar cubes, a relationship between theirstrengths is desired.Two less-common mortar strength tests were used to determine more accurately thecompressive strength of in-situ mortar. The results of both tests were compared to the results ofASTM standard compressive testing with mortars of the same water content. The first was theDouble Punch test which involves the use of two metal punches that compress either side of athin mortar sample till failure. The Double Punch test is more difficult to perform than theASTM standard compression test, but was useful because it simulates the confinement that insitumortar will experience. The Double Punch test was also used with mortar specimens ofvarying thickness to determine a relationship between specimen thickness and compressivestrength. The second test used was the Helix Pullout test. This test is performed by insertingmetal helical screws into a mortar joint, and pulling from the joint while restricting rotation. Themaximum load used to extract the Helix is recorded as the Pullout Load, and is used to find thecompressive strength by use of a calibration curve. This test was used on a masonry wall paneland mortar cubes were also made with the same mortar for compressive testing.The tested mortar exhibited decreased compressive strength with increased water content.The mortar also decreased in strength with increasing specimen thickness. Mortar joints wereshown to be significantly stronger than mortar cubes based on factors of specimen thickness andconfinement by an average factor of at least 2.40. Although results are affected by punchdiameter, the Double Punch test was shown to be a consistent and reliable means of estimatingmortar compressive strength. The Helix Pullout test exhibited wide variation, and wasdetermined to be primarily useful for qualitative comparison as opposed to quantitativedetermination of strength.
197

Development of Novel π-Conjugated Compounds Based on Tripyrrin / トリピリンを基盤とした新規π共役化合物の創出

Umetani, Masataka 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22269号 / 理博第4583号 / 新制||理||1658(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 大須賀 篤弘, 教授 時任 宣博, 教授 依光 英樹 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
198

Ribosomal RNA Mutations that Inhibit the Activity of Transfer-Messenger RNA of Stalled Ribosomes

Crandall, Jacob N. 13 April 2010 (has links)
In eubacteria, stalled ribosomes are rescued by a conserved quality-control mechanism involving transfer-messenger RNA (tmRNA) and its protein partner SmpB. Mimicking a tRNA, tmRNA enters stalled ribosomes, adds Ala to the nascent polypeptide, and serves as a template to encode a short peptide that tags the nascent protein for destruction. To further characterize the tagging process, we developed two genetic selections that link tmRNA activity to cell death. These negative selections can be used to identify inhibitors of tagging or to identify mutations in key residues essential for ribosome rescue. Little is known about which ribosomal elements are specifically required for tmRNA activity. Using these selections, we isolated ribosomal RNA mutations that block the rescue of ribosomes stalled at rare Arg codons or at the inefficient termination signal Pro-opal. We find that deletion of A1150 in the 16S rRNA blocks tagging regardless of the stalling sequence, suggesting that it inhibits tmRNA activity directly. The C889U mutation in 23S rRNA, however, lowers tagging levels at Pro-opal and rare Arg codons but not at the 3'-end of an mRNA lacking a stop codon. We conclude that the C889U mutation does not inhibit tmRNA activity per se but interferes with an upstream step intermediate between stalling and tagging.
199

N-TERMINAL DOMAIN OF rRNA METHYLTRANSFERASE ENZYME RsmC IS IMPORTANT FOR ITS BINDING TO RNA AND RNA CHAPERON ACTIVITY

Kshetri, Man B. 19 May 2021 (has links)
No description available.
200

Design and Synthesis of Substituted 1,4-Hydrazine-linked Piperazine-2,5- and 2,6-diones and 2,5-Terpyrimidinylenes as α-Helical Mimetics

Anderson, Laura 08 July 2009 (has links)
The most common secondary structure of proteins is the alpha-helix. The alpha-helix can be involved in various protein-protein interactions (PPIs) through the recognition of three or more side chains along one face of the alpha-helix (Wells and McClendon, 2007). In recent years, there has been an increasing interest in the development of peptidic and non-peptidic compounds that bind to PPI surfaces. We focused on the design and synthesis of compounds that mimic the orientation of side chain residues of an alpha-helical protein domain. Although our scaffolds could potentially inhibit various PPIs, we focused mainly on the disruption of interactions among the Bcl-2-family of proteins and the Mdm-2-family of proteins to favor apoptosis in cancer cells. A summary of Bcl-2 and Mdm-2 structure and function relationships that focuses on the possibility of using peptidic and non-peptidic alpha-helical mimics as PPI inhibitors is described in Chapter One. Chapter Two discusses the design and synthesis of 3-substituted-2,6- and 2,5-piperazinedione oligomers as more hydrophilic scaffolds compared to previously reported alpha-helical mimetics (Yin, et al., 2005). A key feature of this design is the linkage of the units by a hydrazine bond. While we were able to prepare several monomers containing the hydrazine linkage, synthesis of the dimers and trimers is very challenging. Due to the difficulty of synthesizing oligomeric piperazine-diones in practical yields, we next focused on the design and synthesis of novel 2,5-terpyrimidinylene scaffolds as an alternative to obtain alpha-helical mimetics; this is discussed in Chapter Three. The main outcome of this project was the efficient preparation of a "first-generation" non-peptidic compound library via a facile iterative synthesis enabled by the key conversion of 5-cyanopyrimidine to 5-carboxamidine. Chapter Three also discusses our progress towards the synthesis of structurally similar substituted-2,5-terpyrimidinylenes, but with more drug-like properties as determined by QikProp calculations. Chapter Four describes an independent study on the synthesis of a guanidine derivative as an alkylating agent for the synthesis of cysteine peptide nucleic acids, CPNA, which is another current project in our lab.

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