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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.
161

Funkční charakterizace MDR pumpy Pdr5p zodpovědné za mnohočetnou lékovou rezistenci u kvasinky Saccharomyces cerevisiae / Functional characterization of MDR pump Pdr5p responsible for multiple drug resistance in yeast Saccharomyces cerevisiae

Sayedová, Shirin January 2021 (has links)
One of the main reasons for the treatment failure of infections caused by pathogenic microorganisms is the overexpressing of efflux membrane proteins, which actively remove drugs from cells, leading to a phenomenon called multidrug resistance MDR. In this work, we focused on the functional characterization of the MDR pump Pdr5p in the yeast Saccharomyces cerevisiae. We have verified that diS-C3(3) fluorescence method can be used to determine the binding sites where the substrates bind in the binding pocket of the pump ScPdr5p. We focused on the study of the ScPdr5p binding pocket using triazole derivatives: ravuconazole, voriconazole and fluconazole. Using disc diffusion assay, we showed that all three studied triazoles are substrates of the pump ScPdr5p. We have found that these structural analogs have a significantly different effect on the inhibition of the potentiometric fluorescent probe diS-C3(3) transport by the pump ScPdr5p, and also that ravuconazole and voriconazole compete with each other for transport by the pump ScPdr5p. We have used a fluorescent approach to study the binding of azoles to the binding pocket of pump ScPdr5p using benchmark substrates, that bind selectively to only one binding site in the binding pocket of the pump ScPdr5p, and we have supported the hypothesis that ravuconazole...
162

Možnosti detekce obsahu vody v pórovitém prostředí metodou elektrické impedanční spektrometrie / Possibilities of detection of water content in porous environments using electrical impedance spectrometry method

Fejfarová, Marie January 2014 (has links)
This doctoral thesis with the title “Possibilities of Detecting the Water Content in a Porous Medium Using the Method of Electrical Impedance Spectrometry introduces electrical impedance spectrometry (EIS) as an indirect electrical method of measurement and a tested apparatus for application in water management practice and in material engineering. A wide range of porous media in the area of water management have been narrowed within the preparation of this dissertation thesis to available samples of chiefly sandy soils and in material engineering to typical building materials, which are still solid burnt brick and timber. Measurement took place in the Laboratory of Water Management Research of the Department of Water Structures and in the Laboratory of the Department of Building Materials and Components at the Faculty of Civil Engineering of Brno University of Technology, in the Laboratory of Soil Mechanics of the company GEOtest, a.s. and in the Laboratory of the foreign university KU Leuven, KHBO in the City of Oostende, Belgium. The experiments performed required not only the production of special constructions of measuring probes and their connection, but also modifications of stations at which measurement was carried out. It is possible to use this doctoral dissertation thesis as a methodological manual of how to apply the measuring apparatus based on the EIS method in monitoring changes in the water content in selected porous media due to hydrodynamic stress imposed on it.
163

Metody SPM založené na sondách vyrobených z křemenného rezonátoru / SPM Methods Based On The Quartz Resonator Probes

Wertheimer, Pavel January 2015 (has links)
The thesis is focused on development of scanning probe microscope systems, especially development and implementation of quartz resonator probes. The quartz resonator probes, compared to the standard silicon cantilevers, have several advantages. It is in particular their mechanical properties and possibility of direct electrical readout of the deflection signal. Due to the fact, the probes are easy to implement even into more complex SPM systems. The thesis deals with development of universal and open SPM control system electronics. The electronics consist of the commercial SPM control and oscillation units, the development of the other electronic parts (such as the high voltage amplifier and the preamplifier units) is described in the thesis. Further, the thesis reports on development of the qPlus UHV LT SPM microscope system that was carried out at Universität Hamburg. Part of it was development of the qPlus preamplifier able to operate at liquid helium temperature. The third topic of the thesis is the implementation of qPlus technology into the UHV VT SPM microscope suitable to operate in situ with a scanning electron microscope. The qPlus sensors and the universal UHV preamplifier were designed and manufactured. Test measurements were conducted on all of the developed systems.
164

[en] RAIN VS. MOISTURE RELATIONSHIP IN UNSATURATED SOILS / [pt] RELAÇÃO CHUVA VS. UMIDADE EM SOLOS NÃO SATURADOS

MARCELA STRONGYLIS 21 June 2021 (has links)
[pt] O propósito do trabalho é avaliar a viabilidade técnica do uso de sondas tipo TDR e tensiômetros no monitoramento de encostas não saturadas. Com tais instrumentos, objetiva-se monitorar a variação da sucção mátrica e da umidade no solo em períodos chuvosos, visando aperfeiçoar os sistemas de alerta usados em áreas de risco e, consequentemente, minimizar perdas materiais e humanas. Para as medições, foram instalados uma estação meteorológica (munida de um pluviômetro, um datalogger, uma placa solar e uma antena para a transmissão de dados via internet), quatro sensores de umidade tipo TDR e um tensiômetro de alta capacidade em uma encosta localizada a montante da Faculdade de Medicina de Petrópolis, cidade da região serrana do estado do Rio de Janeiro. Foram registrados cerca de três meses de dados das sondas tipo TDR e, por conta de uma pane elétrica, apenas treze dias de dados do tensiômetro. As sondas tipo TDR apresentaram tempos de resposta rápidos, com nítidos aumentos de umidade volumétrica com o início de um evento chuvoso. Elas também apresentaram sensibilidade adequada para serem utilizadas em sistemas de alerta, sendo capazes de registrar alterações de umidade volumétrica com pequenos volumes de chuva. As curvas características encontradas através de ensaios de papel filtro mostraram um bom paralelo entre as sucções medidas diretamente pelo tensiômetro e aquelas obtidas indiretamente pelas sondas tipo TDR, através da conversão das umidades volumétricas em sucção. / [en] The purpose of this work is to evaluate the technical feasibility of using TDR probes and tensiometers to monitor unsaturated slopes. The objective is to monitor with these instruments the variation of matric suction and soil moisture during rainy periods, aiming to improve the warning systems used in hazardous areas and, consequently, to minimize human and material loss. For the measurements, a meteorological station (equipped with a rain gauge, a datalogger, a solar panel and an antenna for data transmission via internet), four TDR-type humidity sensors and a high capacity tensiometer were installed in a slope located in the University of Medicine of Petrópolis, city of the mountainous region of the state of Rio de Janeiro. Approximately three months of data were collected from the TDR probes and only thirteen days of tensiometer data due to a power outage. TDR-type probes showed fast response time, with clear increases in volumetric humidity with the beginning of a rainfall event. They also showed adequate sensitivity to be used in warning systems, being able to register changes in volumetric humidity with small precipitation amounts. The characteristic curves found by the filter method showed a good correlation with the suctions measured directly by the tensiometer and those obtained indirectly by the TDR probes, by converting the volumetric humidity into suction.
165

Návrh automatizovaného měřicího pracoviště s průmyslovým robotem / Design of measurement robotized workcell

Tvardek, Michal January 2013 (has links)
This master's thesis focuses on the use of the Renishaw's Equator gauging system in cooperation with the industrial robot. The target is to design the robotized workcell which contains these two products. Robot acts as a manipulator for inserting and sorting out the workpieces into the "good" and "bad" pallets according to measured results from the Equator. Equator uses a parallel kinematics and probing system which is normally used on coordinate measuring machines. Therefore there is the introduction to the parallel and serial kinematic structures, to the problems of the coordinate measuring machines in the first part of this thesis. It was made a separation of the probing systems into a few basic categories, description of the typical representatives of these categories and of the other important accessories of the coordinate measuring machines, too. The second part of the thesis contains a description of the Equator gauging system, the industrial robot which I used and their accessories. In this part is mentioned a few examples of measurement automation in industry practice, too. The third part devotes to the design of the robotized workcell and contains all the important requirements for the realization.
166

Análisis del estatuto jurídico de compras públicas en Chile y su relación con la normativa y principios de defensa de la libre competencia

Ayala Castro, Jaime Antonio January 2016 (has links)
Memoria (licenciado en ciencias jurídicas y sociales) / Con ocasión de los múltiples casos conocidos por el Tribunal de Defensa de la Libre Competencia en Chile en materia de contratación pública, este trabajo se centra, en primer lugar, en el análisis de las interacciones que existen entre ambos sectores de nuestro ordenamiento jurídico tanto a nivel dogmático –por la vía de los principios consagrados por la Constitución Política de la República de Chile– como a nivel legal y reglamentario –las que, como demostraremos, son escasas– a fin de escudriñar cómo los entes legislativos han dado reconocimiento expreso o tácito a tal vinculación. En segundo lugar, y a efectos de demostrar la necesidad de que ambos estatutos jurídicos se relacionen de forma más íntima y expresa, señalamos algunos pronunciamientos judiciales y doctrinales que explican cómo hacer aplicable, por la vía del principio de juridicidad administrativa, la obligación de observar por parte de todos los órganos de la Administración del Estado, en todas sus actuaciones, las normas contenidas en el DL 211. En tercer lugar, identificamos los casos en que el H. Tribunal de Defensa de la Libre Competencia ha emitido pronunciamientos respecto de conductas anticompetitivas en el marco de procesos de licitación regidos por la Ley N° 19.886, conociendo y resolviendo demandas incoadas por particulares y requerimientos interpuestos por la Fiscalía Nacional Económica en contra de diversos órganos administrativos licitantes, a fin de extraer de ellos los criterios que dicho Tribunal ha aplicado. Enseguida, expondremos algunas directrices que el ente persecutor de infracciones a la libre competencia en Chile, la FNE, ha recomendado a la Administración para, preventivamente, evitar conductas anticompetitivas y también ciertos lineamientos que la Organización para la Cooperación y el Desarrollo Económico (OCDE) ha aconsejado para resguardar la competencia en procesos licitatorios. Por último, hemos escogido un caso de cierta relevancia mediática y relativamente reciente para ser analizado a la luz de todos los planteamientos que se expusieron a lo largo del trabajo, cual es el de Sonda con Registro Civil, en el marco de la licitación para la provisión de servicios de identificación personal.
167

Srovnávací analýza příloh celostátních deníků Salon, Kavárna, Orientace / Comparative analysis of the national newspaper supplements Salon, Kavarna and Orientace

Farná, Kateřina January 2010 (has links)
Diploma thesis "Comparison analyses of national newspaper supplements Salon, Kavarna and Orientace" analyses supplements of national, daily released newspapers: Pravo (Salon), Mlada fronta DNES (Kavarna) and Lidove noviny (Orientace). Essential methods used in this work are quantitative analysis, applied to specified moths during years 2006-2008, and chronological analysis of chosen issues during years 1998, 1999, 2000 and 2005. Based on them, various evaluations of supplement main characteristics, specific features and differences were observed. Most important characteristics investigated in the work are: supplement content and graphic conception, placement within the carrying newspaper, structure of published literature forms, themes and sub-themes. There can be also found summary of each supplement history, list of its typical authors and internet version description. Author of this thesis also introduced related overview of Czech literary and cultural magazines (Literarni noviny, Host, Divoke vino, Revolver Revue, Tvar nebo A2) and briefly stated profiles of main national newspapers. To gain supplement readers characteristics, approximate sociological questionnaire was processed among university students.
168

Avaliação da esterilidade dos instrumentais laparoscópicos de uso único reprocessados após contaminação artificial / Sterility evaluation of single use laparoscopic devices reprocessed after artificial contamination

Lopes, Cristiane de Lion Botero Couto 20 December 2006 (has links)
Os materiais de uso único (MUU) são utilizados há décadas na assistência à saúde. Inicialmente produzidos com a finalidade de prontamente disponibilizar os materiais para uso na assistência a saúde e ao mesmo tempo diminuir a sobrecarga com o trabalho inerente ao reprocessamento dos materiais. Com o passar do tempo, principalmente por questões financeiras, estes passaram a ser reutilizados. A partir de então diversos questionamentos têm sido suscitados a respeito do risco de transmissão de infecção pelo reuso destes artigos em decorrência da dificuldade para de limpeza, desinfecção e esterilização seguras destes. Os materiais utilizados para as cirurgias vídeo-laparoscópicas encontram-se entre os MUU de preço considerável e complexidade importante em relação às dificuldades para limpeza, devido à sua conformação com espaços internos inacessíveis e impossibilidade de desmonte. Isto posto, as pinças grasper, dissector, tesoura, agulha de Veress, sistema de sonda de eletrocirurgia (ou aspirador e irrigador) e sua respectiva haste, instrumentais básicos nos procedimentos de vídeo-cirurgia-laparoscópica, foram o objeto desta investigação com o propósito de avaliar a eficácia da esterilidade destes acessórios de uso único após contaminação artificial desafio e comparar os resultados dos testes de esterilidade dos MUU com os dos materiais equivalentes reprocessáveis – denominados neste estudo como grupo controle. Tratou-se de uma pesquisa experimental, laboratorial e comparativa. O inóculo utilizado para a contaminação artificial dos instrumentais de uso único constituiu-se de suspensão de esporos bacterianos do Bacillus atrophaeus var. niger e de sangue de carneiro desfibrinado esterilizado. Para o grupo controle o microrganismo eleito foi o Geobacillus stearothermophilus acrescido também de sangue de carneiro desfibrinado. Antes de proceder aos experimentos validou-se a metodologia analítica em duas fases: fase 1 - realizada a contagem de U.F.C. em três unidades de cada um dos materiais dos grupos experimental e controle após a contaminação artificial antecedendo a limpeza; fase 2 - realizada a contagem de U.F.C. em três unidades de cada um dos materiais dos grupos experimental e controle após a contaminação artificial e procedimento de limpeza. Desta forma, assegurada a recuperação dos contaminantes em todas as amostras da primeira fase e a diminuição do bioburden inicial após a limpeza dos instrumentais na 2ª fase, deu-se prosseguimento aos experimentos. Os materiais laparoscópicos foram intencionalmente contaminados com o inóculo desafio e submetidos após ao protocolo teste para validação que consistiu da seguinte seqüência: limpeza automatizada em lavadora ultra-sônica com retrofluxo com auxílio do detergente enzimático, limpeza manual complementar com serpilhos e irrigação dos lumens dos instrumentais com água sob pressão. Por fim, foi realizado o enxágüe com água destilada esterilizada, secagem com ar comprimido medicinal, acondicionamento em embalagem de papel grau cirúrgico e filme e submetidos a esterilização em Óxido de Etileno 12/88 (materiais de uso único) e em autoclave (materiais de aço inoxidável). Os materiais esterilizados foram inoculados diretamente nos meios de cultura de caseína soja e incubados por 20 dias quando foi feita a leitura final dos resultados das culturas. Os resultados encontrados foram 100% negativos para a recuperação dos microrganismos contaminantes nos 2 grupos - experimental e controle. Estes achados permitiram concluir que o reprocessamento dos materiais de uso único foi validado em relação à esterilidade permitindo chegar a um protocolo de reprocessamento / Single use devices (SUD) have been used in healthcare for decades. They were initially produced for making them readily available for use in healthcare and at the same time lower the inherent workload for device reprocessing. After time, mainly for financial reasons, they became reused. Since then, several questioning has been raised regarding to the risk of infection transmission by reusing these devices due to their difficulty of safe cleaning, disinfection and sterilization. Devices used for videosurgeries are among the SUD of considerable price and important complexity due to cleaning difficulties, because of their adjustments in inaccessible inner spaces and impossibility of taking them out into pieces. Thus, grasper calipers, dissecting forceps, scissors, Veress insuflation needle, electrosurgery probe system (or suction and irrigation tubes) and its respective dissector cannula, basic devices in videosurgery laparoscopic procedures were all the subject of investigation aimed to evaluate the effectiveness of sterility of these single use products after challenged artificial contamination and comparing the results of sterility tests of SUD to their equivalent reprocessed devices – named in this study as control group. It’s a comparative, laboratory experimental research. The inoculum used for artificial contamination of single use devices was the suspension of Bacillus atrophaeus var. niger bacteria spores and sterilized defibrinated sheep blood. For the control group, the elected strain was Geobacillus stearothermophilus adding also the defibrinated sheep blood. Before carrying out the experiments, the analytical methodology was validated in two phases: phase 1 – counting the colony formation units in three units of each one of the devices from the experimental and control groups after the artificial contamination and cleaning procedures. This way, assured the contaminant recovery in all samples of the 1st phase and the reduction of initial bioburden after device cleaning in the 2nd phase, it was carried on the experiments. The laparoscopic devices were intentionally contaminated with challenged inoculum and submitted after the trial test to validation that was consisted of the following sequence: cleaning in automated narrow-lumen cleaner with enzymatic detergent, complementary manual cleaning with brush and lumen washing of devices with water under pressure. At last, it was made rinsing with sterile distillated water, drying with medical compressed air, packing in surgical paper and film wrapping and submitted to sterilization in ethylene oxide 12/88 (single use devices) and in autoclave (stainless steel devices). The sterilized devices were contaminated directly in the casein soy media and incubated for 20 days when it was made the final reading of media results. The outcomes found were 100% negative for recovering of contamination strains in the 2 groups – the experimental and the control. These findings permitted us to conclude that single use device reprocessing was validated regarding to sterility allowing us to get a reprocessing guideline
169

Desenvolvimento de uma sonda TDR helicoidal para uso em conjunto com o ensaio CPT / Developing a coil TDR probe to use together with the CPT test

Guerrero Doria, Katerin 21 August 2015 (has links)
A reflectometria no domínio do tempo permite estimar o teor de umidade de um meio através da sua correlação com a constante dielétrica. Uma sonda helicoidal TDR, que pode ser cravada em conjunto outros ensaios de penetração in situ para a estimativa do teor de umidade em diversas profundidades, tem aplicação interessante para a investigação geotécnica do subsolo. No presente trabalho, uma sonda TDR foi adaptada e utilizada em conjunto ao ensaio CPT para caracterização de um perfil de solo arenoso não saturado que ocorre na região de Bauru (SP). A calibração dessa sonda foi feita em laboratório especificamente para esse solo. As equações de calibração que mostraram os melhores resultados foram definidas correlacionando a constante dielétrica, condutividade elétrica aparente e a massa específica seca com o teor de umidade. Com o intuito de melhorar a acurácia na determinação do teor de umidade em campo e eliminar possíveis interferências no registro da onda eletromagnética, foram efetuadas modificações em algumas características do projeto original dessa sonda. Tais modificações consistiram em separar os eletrodos condutores e as partes metálicas da sonda, e eliminar o cabo coaxial de extensão, conectando a sonda diretamente a um cabo coaxial de 12 m de comprimento. Tais mudanças levaram a uma melhoria significativa na determinação do perfil de teor de umidade do local estudado. Os valores de teor de umidade de campo determinados usando o TDR ao longo de 8 m de profundidade foram comparados com os valores de referência obtidos de amostras deformadas retiradas com trado mecânico. O erro médio na estimativa do perfil de teor de umidade gravimétrico utilizando a sonda TDR helicoidal foi de 1.61%, na última campanha de ensaios realizados. Os resultados dessa pesquisa indicam que esta ferramenta é adequada para estimar do perfil de teor de umidade para uso em conjunto com o ensaio CPT. / The time domain reflectometry allows estimating the moisture content of a medium by means of its correlation with the dielectric constant. A coil TDR probe, which can be driven into the ground together with others in situ penetration tests, can be used to estimate the moisture content at different depths. It is an interesting approach for geotechnical site characterization. In this work, a coil TDR probe was adapted and used in combination with the CPT test for the site characterization of an unsaturated sandy soil profile which occurs in the region of Bauru (SP). The probe calibration was performed in laboratory specifically for that soil. The calibration equation, which presented the best results, were defined correlating the dielectric constant, electrical conductivity and dry density with the moisture content. In order to improve the accuracy for determining the water content in the field and to eliminate possible interference on the electromagnetic wave registration, modifications were made in some characteristics of the original design of this probe. Such modifications consisted in separating the conductive electrodes from the metal parts of the probe, and eliminating the coaxial extension cable, connecting the probe directly to a coaxial cable 12 m long. Such changes have led to a significant improvement in the determination of the moisture content profile of the studied site. The moisture content values determined in situ by using the TDR along 8 m depth were compared with reference values obtained from disturbed soil samples collected using mechanical augers. The root mean square error of the gravimetric water content profile using the TDR coil probe was 1.61% in the last test campaign. The results of this research indicate that this tool is suitable to estimate the gravimetric moisture content together with the CPT test.
170

Análise da operação de sistemas de potência isolados para plataformas flutuantes / Analysis of isolated power systems operation for floating platforms.

Almeida, Bruno de 29 July 2019 (has links)
Este trabalho apresenta a modelagem do sistema elétrico de potência de uma plataforma de perfuração dotada de sistema de posicionamento dinâmico. Para tanto, inicialmente são apresentados os conceitos fundamentais de tais unidades, servindo como base teórica e justificando a necessidade de tal estudo. Posteriormente, são apresentados de forma mais detalhada os sistemas de propulsão e geração com as respectivas estratégias de controle. Para a propulsão, estes são acionados por motores de indução trifásicos tendo velocidade controlada a partir da estratégia Direct Torque Control utilizando inversores de três níveis. Para a geração, são utilizados motores diesel como máquinas primárias acoplados a geradores síncronos trifásicos, juntamente com seus respectivos reguladores de velocidade e de tensão. Primeiramente, a operacionalidade destes modelos propostos é confirmada a partir de simulações no programa computacional MATLABR®, utilizando-se a ferramenta gráfica Simulink. Na sequência, a modelagem do sistema de potência completo é obtida no mesmo programa computacional, onde são incluídos os devidos cabeamentos, transformadores e cargas dinâmicas representando os equipamentos de perfuração e de baixa tensão. Utilizando-se de patamares de carga e comandos de velocidade de propulsores obtidos de uma plataforma real em operação de perfuração são realizadas simulações neste sistema completo, tanto com os barramentos de alta tensão interligados quanto segregados. Dentre os resultados obtidos, observa-se que os controles de tensão e de frequência são adequados, além da correta divisão de carga entre geradores a partir do método droop compensado. Por fim, com o intuito de mostrar a potencialidade do sistema obtido, são realizadas análises de curto-circuito mantendo os barramentos de alta tensão interligados, onde é possível observar a propagação da queda de tensão quando a falta ocorre em um barramento de baixa tensão, além das consequências para todo o sistema quando tais faltas são aplicadas no nível de alta tensão. / This work presents the electrical power system modeling of a drilling rig equipped with a dynamic positioning system. Initially, fundamental concepts of such units are presented, bringing a theoretical basis and justifying the need for this study. Subsequently, the propulsion and generation systems as well as their respective control strategies are presented in detail. In regard to the thrusters, they are driven by three-phase induction motors and their speed are controlled by Direct Torque Control strategy using three-level inverters. In respect of the generation system, the prime movers are modeled as diesel engines coupled to three-phase synchronous generators, in addition to their respective speed and voltage regulators. Firstly, the functionality of the proposed models is confirmed by simulations in MATLABR® using Simulink graphical tool. After, the modeling of the complete power system is obtained on the same software, which considers the inclusion of appropriate wiring, transformers and dynamic loads representing the drilling and low voltage equipment. By using load levels and thruster speed commands from an actual vessel during a drilling operation, simulations are carried out at the complete system, considering the high voltage busbars at either connected or segregated configuration. Among the obtained results, it is possible to observe suitable voltage and frequency controls, besides the correct generators load sharing in compensated droop mode. Lastly, to present the potentiality of the obtained system, a short-circuit analysis is performed with the high voltage busbars connected, where it is noticed the means of the voltage drop propagates through the system when the fault occurs at a low voltage busbar, besides the consequences when similar faults are applied at the high voltage level.

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