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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.
221

Estudo da utilização de nanotubos de carbono como adjuvante em Vacinas de membrana externa de Neisseria meningitidis = Analysis of the use of carbon nanotubes as adjuvant in outer membrane vaccines from Neisseria meningitidis / Analysis of the use of carbon nanotubes as adjuvant in outer membrane vaccines from Neisseria meningitidis

Mattos, Ives Bernardelli de, 1985- 23 August 2018 (has links)
Orientador: Marcelo Lancellotti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T11:46:02Z (GMT). No. of bitstreams: 1 Mattos_IvesBernardellide_M.pdf: 15060536 bytes, checksum: 32a633419d15c105fec735cb5753d5b2 (MD5) Previous issue date: 2012 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital quando liberada / Abstract: The abstract is available with the full electronic document when available / Mestrado / Bioquimica / Mestre em Biologia Funcional e Molecular
222

Temperature-inducible and calcium-regulated proteins encoded by the virulence plasmid of Yersinia

Bölin, Ingrid January 1987 (has links)
The pathogenic members of the genus Yersinia, Y. pseudotuberculosis, Y. pestis and Y. enterocolitica are transmitted from animals to man and may give rise to disease with a variety of symptoms. These bacteria possess related plasmids necessary for virulence. In this study, gene products encoded by the virulence plasmid have been identified and characterized. A temperature-inducible outer membrane protein YOP1, is encoded by the virulence plasmid. YOP1 is expressed by Y. pseudotuberculosis and Y. enterocolitica at 37°C. The genetic locale of trie structural gene for YOPl on the virulence plasmid was determined. A mutant that was unable to express this protein, remained fully virulent, showing that YOP1 is not a virulence determinant. Several other proteins encoded by the virulence plasmid are induced at 37°C in a medium lacking Ca2+. These proteins are not expressed at 26°C and expression is repressed by Ca2+-concentrations in excess of 2.5 mM. In Ca2+-deficient medium, the induced proteins can be found extracellu- larly as well as in the outer membrane. However, in the presence of Ca at 37°C they are only found in the outer membrane. The released proteins consist of eight polypeptides as revealed by two-dimensional electro­phoresis. These proteins, Y0P2a and 2b, YOP3, Y0P4a and 4b, the V-antigen and a small uncharacterized polypeptide, are expressed by all three pathogenic Yersinia species, both in vivo and in vitro. The Ca2+-controlled expression of the YOP proteins is regulated by genes in the Ca2+ -region, which are conserved in the three species. Mutations in this region repress the expression of the Ca2+-regulated YOPs. The genetic loci identified for five of these proteins revealed that only the structural gene of the Y0P4b protein is part of the Ca2+ -region. The other genes were found at separate locations outside this region. The structural genes for YOP4b, YOP3 and the V-antigen, together with the genes for two additional polypeptides, were localized to a common region conserved on the plasmids of the Yersinia species. The structural genes for Y0P2b (yopH) and Y0P5 (yopE) are located in different positions on the plasmid from Y. enterocolitica, compared to the other two species. This plasmid has Been rearranged so that these genes are located close to one another. The DNA sequence of the yopH gene shows that it is a singly transcrip­tional unit. Transcription of this gene is regulated by Ca2+-concentra­tion and by temperature. A mutant strain of Y. pseudo tuberculosis, de­leted for the yopH gene on the virulence plasmid, is avirulent In mice. Virulence is restored by trans-complementation with the cloned yopH gene. The mutant strain is also’ unable to inhibit phagocytosis of macrophages as compared to the wild-type strain. The trans-compleroented strain shows inhibition comparable to that of the wild-type. Therefore, the YOP2b protein is considered to be an essential virulence determinant. / digitalisering@umu.se
223

Strategická analýza Nemocnice Jihlava / Strategic Analysis of Jihlava Hospital

Kolman, Vojtěch January 2010 (has links)
The aim of this thesis is to formulate a strategic analysis of the Hospital Jihlava. The founder of the hospital is region Vysočina. This hospital provides comprehensive health services. The operating space is defined by region. The current competitors of this hospital are hospitals Trebic, Havlickuv Brod, Nove Mesto in Moravia, Pelhřimov and Hospital St. Zdislavy, Inc. The strengths of the hospital include its location, status of "regional" hospitals, complexity of services offered, rich history and uniqueness of certain resources. Among the weaknesses of the hospital include poor economic situation, bad strategy, ineffective management, administrative burden, lack of promotion, lack of motivation and poor awareness of employees. Based on the analysis will be proposed the recommendation at the end of this work.
224

The identification of a multi-ethnic South African typology

Corder, Clive Kingsmill 22 July 2002 (has links)
The aim of this study was to discover whether a value-based typology could be established that was applicable to all South African adults. It was predicated on the basis of a literature review and previous research findings that there were two major underlying dimensions of values: collectivism versus individualism and inner- versus outer-directed. The parameters of these dimensions were hypothesised within the framework of a common social structure, based on a number of related propositions. It was also hypothesised that the South African adult population consisted of five types. Five value measures were examined and found to have disadvantages for South Africa. A value measurement technique had been developed in South Africa for an on-going study titled Sociomonitor. The core of this study was the measurement of values of relevance to marketing and media. Over the period 1976 to 1993 separate value based typologies were identified for urban Blacks and Whites. In 1995 both races were covered in the same year and a common typology was found. In 1997/8 Sociomonitor was extended to the total adult population of South Africa. Respondents were sub-divided into Collectivism, Individualism, Inner- and Outer-directed groups. The characteristics of which were found to be substantially as had been expected. South African adults were categorised into five value types. Three of which were as had been hypothesised, two were in place of one of the five anticipated and one wasn't found. It is concluded that the values of adults from all ethnic groups fall within the parameters of collectivism versus individualism and inner- versus outer-directed. Furthermore, there are five different value types in the South African adult population that transcend ethnic boundaries. The implications of a multi-ethnic typology for marketing, social and political decision-making, research and the formulation of scenarios are outlined. It is recommended that this type of research be extended to other African countries and small communities. / Dissertation (PHD)--University of Pretoria, 2003. / Psychology / unrestricted
225

Cinética do cultivo em biorreator de Niesseria meningitidis sorogrupo B / Bioreactor cultivation kinetics of group B Neisseria meningitidis

Silvia Santos 13 August 2007 (has links)
Neisseria meningitidis B libera vesículas de membrana externa, conhecidas pela sigla OMV. Essas possuem os mesmos componentes da membrana externa da bactéria e podem ser utilizadas como antígenos em vacinas contra a meningite B. As vesículas devem, também, expressar proteínas da membrana externa (OMP) e proteínas reguladoras do íon ferro (IRP). O objetivo deste trabalho é estudar a cinética de crescimento bacteriano, consumo das fontes de carbono e nitrogênio - especialmente os limitantes de crescimento ? e produção de OMV visando melhorar a produção desse antígeno. Realizaram-se cultivos descontínuos em biorreator, com duração de 20 h, empregando meio de Catlin com limitação de ferro e modificações nas concentrações de lactato, aminoácidos e glicerol. As condições do cultivo foram: 4,2 L de meio, temperatura de 36°C, pressão de 0,5 atm, vazão de ar 1 L/min, agitação entre 250-850 rpm, controle de oxigênio dissolvido em 10% de saturação. Constatou-se que o lactato é a principal fonte de carbono limitante, embora somente se tem a hipótese de que o glicerol age como protetor mecânico. O ácido L-glutâmico é a principal fonte de nitrogênio consumida durante o cultivo. As OMV começaram a ser liberadas quantitativamente no início da fase estacionária de crescimento. Sendo que a melhor condição para a produção de OMV, valor 162,3 mg/L, é aquela em que as concentrações iniciais de lactato e aminoácidos foram duplicadas, 15,00 g/L e 2,93 g/L respectivamente. Através da análise do padrão eletroforético, confirmou-se a presença das principais proteínas de superfície, inclusive das IRPs. A integridade da OMV foi constatada por microscopia eletrônica. Assim, o antígeno obtido mostra-se passível de utilização na composição de vacina anti-meningocócica. / Neisseria meningitidis B liberates outer membrane vesicles known by the abbreviation OMV. These vesicles have the same components of the outer membrane of the bacteria and may be used as antigens in vaccines against meningitis B. The vesicles must also express outer membrane proteins (OMP) and iron regulated proteins (IRP). The aim of this paper is to study bacterial growth kinetics, carbon and nitrogen sources consumption ? specially those which limit growth ? and OMV production, seeking to improve the production of this antigen. Discontinuous bioreactor cultivations were carried out for a period of 20 hours in Catlin medium with iron restriction and modifications in lactate, amino acid, and glycerol concentrations. Cultivation conditions were: 4,2 L of medium, temperature at 36ºC, 0,5 atm, air flow rate of 1 L/min, agitation between 250-850 rpm, and dissolved oxygen control at 10% of saturation. It was verified that lactate is the main limiting carbon source, although there is just a hypothesis that glycerol acts as a mechanic protector. The L-glutamic acid is the main source of nitrogen consumed during the cultivation. The OMV started to be liberated quantitatively at the beginning of the stationary phase of growth. The best condition for production of OMV, value 162,3 mg/L, is that where the initial concentrations of lactate and amino acids were duplicated, 15,00 g/L and 2,93 g/L, respectively. Through an analysis of the electroforetic pattern, the presence of the main surface proteins was confirmed, including the IRPs. The integrity of the OMV was testified by electronic microscopy. So, the antigen thus obtained may be used in the antimeningococcal vaccine composition.
226

Marketingová strategie společnosti / Marketing Strategy of Company

Koláček, Tomáš January 2010 (has links)
The aim of this diploma thesis is propose a way to create a marketing strategy for the young company in the media & marketing market. This diploma thesis describes the use of key techniques, basic theoretical assumptions and their physical implementation of theoretical methods and support methods in connection with the topic of work developed under analysis.
227

Effet du rayonnement cosmique galactique sur les petits corps glacés du système solaire externe : indices pour la formation de la matière organique des micrométéorites antarctiques ultra-carbonées / Effects of galactic cosmic rays on the surface of icy bodies from the outer solar system : clues for the formation of organic matter found in ultracarbonaceous antarctica micrometeorites

Auge, Basile 12 October 2017 (has links)
Les météorites et particules de poussière interplanétaire apportent des contraintes sur la formation et l’évolution de la matière dans le système solaire. Les micrométéorites, dont certaines proviennent des régions externes du système solaire, représentent la source dominante de matière extraterrestre arrivant sur Terre. Les micrométéorites collectées dans les neiges antarctiques sont dans un excellent état de conservation du fait de conditions géographiques et météorologiques favorables à leur préservation. La collection CONCORDIA/CSNSM de micrométéorites contient en particulier des micrométéorites peu altérées thermiquement lors de leur entrée atmosphérique. Certaines sont caractérisées par une très haute teneur en matière organique, dépassant 50% en volume, très largement au dessus des valeurs habituelles trouvées dans les météorites. Cette matière organique présente de plus la spécificité d’être fortement enrichie en deutérium et contient jusqu’à cinq fois plus d’azote celle extraite des météorites.Les différents scénarios proposés pour expliquer la formation de cette matière et satisfaisant à l’ensemble des caractéristiques de ces micrométéorites impliquent des corps parents orbitant au-delà de Neptune, dans la ceinture de Kuiper ou dans le nuage de Oort. La température y est suffisamment basse pour condenser à leur surface les molécules volatiles comme l’azote et le méthane tandis qu’ils sont exposés à l’action radiochimique du rayonnement cosmique galactique. Afin de contraindre ces scénarios, des expériences ont été conduites en exposant différentes glaces N2-CH4 aux faisceaux d’ions du GANIL simulant ce rayonnement. L’évolution chimique des glaces au cours de l’irradiation et pendant le recuit des échantillons a été suivie par spectroscopie infrarouge au moyen de deux dispositifs disponibles au CIMAP : la chambre d’analyse CASIMIR et le nouvel appareil IGLIAS. Des analyses complémentaires ex situ ont été menées par spectrométrie de masse. Les résultats apportant des éléments de réponse à l’origine de la matière organique des micrométéorites ultracarbonées ainsi que sur l’origine de leur enrichissement isotopique seront présentés et discutés. / Extraterrestrial materials, such as meteorites and interplanetary dust particles, provide constraints on the formation and evolution of organic matter in the young solar system. Micrometeorites represent the dominant source of extraterrestrial matter at the Earth’s surface, some of them originating from large heliocentric distances.Micrometeorites recovered from Antarctica snows provide a unique source of pristine interplanetary dust particles, which underwent a minimal weathering at atmospheric entry. A few percent are characterized by very large carbon content with at least 50% in volume, much higher than the value found in meteorites. This organic matter exhibits extreme deuterium excesses and is unusually nitrogen-rich.Several formation scenarios have been proposed for the formation of the N-rich organic matter observed in UCAMMs, suggesting that these particles come from a parent body orbiting beyond the nitrogen snow line, in the outer Solar System where they are exposed to ions from the galactic cosmic rays. We experimentally evaluate the scenario involving high energy irradiation of icy bodies subsurface orbiting at large heliocentric distances by irradiating N2-CH4 ices with swift heavy ions provided by the GANIL facility. Chemical evolution was monitored by Fourier transform infrared spectroscopy with two experimental set-up : CASIMIR and IGLIAS. Ex situ mass spectroscopy measurement where also conducted. Results concerning the origin of the organic matter found in ultracarbonaceous micrometeorites and the origin of its deuterium enrichment will be presented and discussed.
228

Koncept bezpečnostního dilematu v aplikaci na prostředí vesmíru: případ navigačního systému Galileo / The concept of security dilemma in the environment of outer space: the case of the Galileo system

Němečková, Marie January 2020 (has links)
This diploma thesis applies the well-established concept of security dilemma to the relatively new domain of outer space. It constructs a comprehensive modification of the concept for the outer space - the space security dilemma - and establishes criteria for the assessment of it while also discussing previous approaches. The thesis then applies this concept and established criteria, to the issue of Global Navigation Satellite Systems (GNSS). More specifically, it focuses on the case of the European GNSS called Galileo and assesses the intentions behind its creation. Through this assessment, the thesis focuses on determining whether the European Union became a space security dilemma initiator by the development of the Galileo system. In order to confront the theoretical conclusions with praxis, the thesis then focuses on the case of the United States of America and the confrontation between GPS and Galileo. In its last chapter, the thesis replicates this approach on the cases of the Russian Federation (and its GLONASS) and the People's Republic of China (and its BeiDou/COMPASS).
229

Studio class purpose for performance : A comparison on how a musical piece performed in a final recital concert is different when prepared in studio class

Tupina, Madara January 2022 (has links)
The purpose of this thesis was to find out if and how studio class improves a live performance at a final examination concert. Although the specific research described in this paper was about playing the viola, the argument is made that the exploration and knowledge of pratice would be of benefit to any musician. This paper describes the studio class experiment during an academic semester within playing a musical piece and its full analysis. Information is provided about the studio class, its methods, variations, and practices. The application of studio class at the Royal College of Music in Stockholm to viola playing in general is discussed, and specifically to the preparation for the performance of Sonata for viola and piano by Janis Medins. The results of the study indicates that studio class was really beneficial to the interpretation of the piece during a live performance at a final examination concert. / <p>Janis Medins, Sonata for viola and piano (1959)</p>
230

Modulation of conformational space and dynamics of unfolded outer membrane proteins by periplasmic chaperones

Chamachi, Neharika 03 June 2021 (has links)
Beta-barrel outer membrane proteins (OMPs) present on the outer membrane of Gram-negative bacteria are vital to cell survival. Their biogenesis is a challenging process which is tightly regulated by protein-chaperone interactions at various stages. Upon secretion from the inner membrane, OMPs are solubilized by periplasmic chaperones seventeen kilodalton protein (Skp) and survival factor A (SurA) and maintained in a folding competent state until they reach the outer membrane. As periplasm has an energy deficient environment, thermodynamics plays an important role in fine tuning these chaperone-OMP interactions. Thus, a complete understanding of such associations necessitates an investigation into both structural and thermodynamic aspects of the underlying intercommunication. Yet, they have been difficult to discern because of the conformational heterogeneity of the bound substrates, fast chain dynamics and the aggregation prone nature of OMPs. This demands for use of single molecule spectroscopy techniques, specifically, single molecule Förster resonance energy transfer (smFRET). In this thesis, upon leveraging the conformational and temporal resolution offered by smFRET, an exciting insight is obtained into the mechanistic and functional features of unfolded and Skp/SurA - bound states of two differently sized OMPs: OmpX (8 β-strands) and outer membrane phospholipase A (OmpLA – 12 β-strands). First, it was elucidated that the unfolded states of both the proteins exhibit slow interconversion within their sub-populations. Remarkably, upon complexing with chaperones, irrespective of the chosen OMP, the bound substrates expanded with localised chain reconfiguration on a sub-millisecond timescale. Yet, due to the different interaction mechanisms employed by Skp (encapsulation) and SurA (multivalent binding), their clients were found to be characterised by distinct conformational ensembles. Importantly, the extracted thermodynamic parameters of change in enthalpy and entropy exemplified the mechanistically dissimilar functionalities of the two chaperones. Furthermore, both Skp and SurA were found to be capable of disintegrating aggregated OMPs rather cooperatively, highlighting their multifaceted chaperone activity. This work is of significant fundamental value towards understanding the ubiquitous chaperone-protein interactions and opens up the possibility to design drugs targeting the chaperone-OMP complex itself, one step ahead of the OMP assembly on the outer membrane.

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