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1
Zbede, Yaman. "Model predictive MRAS estimator for sensorless induction motor drives." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3771.
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The project presents a novel model predictive reference adaptive system (MRAS) speed observer for sensorless induction motor drives applications. The proposed observer is based on the finite control set-model predictive control principle. The rotor position is calculated using a search-based optimization algorithm which ensures a minimum speed tuning error signal at each sampling period. This eliminates the need for a proportional integral (PI) controller which is conventionally employed in the adaption mechanism of MRAS observers. Extensive simulation and experimental tests have been carried out to evaluate the performance of the proposed observer. Both the simulation and the experimental results show improved performance of the MRAS scheme in both open and closed-loop sensorless modes of operation at low speeds and with different loading conditions including regeneration. The proposed scheme also improves the system robustness against motor parameter variations and increases the maximum bandwidth of the speed loop controller. However, some of the experimental results show oscillations in the estimated rotor speed, especially at light loading conditions. Furthermore, due to the use of the voltage equation in the reference model, the scheme remains sensitive, to a certain extent, to the variations in the machine parameters. Therefore, to reduce rotor speed oscillations at light loading conditions, an adaptive filter is employed in the speed extraction mechanism, where an adaptation mechanism is proposed to adapt the filter time constant depending on the dynamic state of the system. Furthermore, a voltage compensating method is employed in the reference model of the MP-MRAS observer to address the problems associated with sensitivity to motor parameter variation. The performance of the proposed scheme is evaluated both experimentally and by simulation. Results confirm the effectiveness of the proposed scheme for sensorless speed control of IM drives.
2
Yang, Chao. "Speed Sensorless Control for Induction Motor Drives with AI-Based MRAS." Thesis, University of Newcastle Upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525087.
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Shiref, Muez. "Investigation into PI controller output ripple in MRAS based electrical drives." Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2264.
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In Sensorless speed drives, which employ a model reference adaptive system (MRAS) with a PI based adaptation mechanism, the gains of the adaptation mechanism play an important role into the general performance of the drives. The higher the gain, the faster the response and the more robust the drive is going to be against load disturbance. Although it is desirable to utilise an adaptation mechanism with high PI gains, it was demonstrated that high gains will cause the estimated speed to exhibit a high level of noise. More recently it was identified that the generated noise consists of high-order harmonics. As far as the literature is concerned, even though the high-order harmonic phenomenon was identified and addressed by few researchers, there was no description in their literature of the generated high-order harmonics or an assessment of their effect in terms of being problematic. Therefore, the aim of this research is to not only investigate the generation of high-order harmonics, but also to establish whether any generated noise in the estimated speed bear an effect on the overall speed estimation process. An MRAS based speed estimator is implemented to calculate the rotor flux- linkage and the speed estimates required in achieving field orientation and establishing speed control. An investigation has been carried out to gauge how the PI controller gains can influence the speed estimation process of the drive system. As well as examining the estimated speed for any trace of excessive noise and harmonics generation. It is revealed experimentally that no high-order harmonics were generated while implementing an adaptation mechanism with high PI gains. However, it was found that high PI gains do causes the estimated speed to become relatively noisy and also starts to carry some fundamental frequency components relevant to the stator’s electrical frequency. Therefore a programmable adaptive adjustment mechanism has been successfully developed not only to avoid the excessive generation of noise but also improve the speed estimation process. The performance of both of the static adaptation mechanism and the proposed adaptive one was assessed and compared.
4
Mathieu, Marie-Emmanuelle. "Etude de la balance pluripotence-differenciation des cellules souches embryonnaires murines sous l'effet du LIF : rôle du gène MRAS." Thesis, Bordeaux 2, 2011. http://www.theses.fr/2011BOR21878/document.
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Le LIF (Leukemia Inhibitory factor), une cytokine de la famille de l’Interleukine 6, permet le maintien de la pluripotence des cellules souches embryonnaires murines (CSEm) in vitro. Dans le but de comprendre les mécanismes d’action du LIF dans ce modèle d’étude, une analyse sur puces à ADN a été réalisée et a permis d’identifier trois « signatures LIF » : les gènes « Pluri » (pour Pluripotence), dont le niveau d’expression relatif chute suite au retrait de cette cytokine, et deux catégories de gènes « Lifind » (pour LIF induit) dont le niveau d’expression relatif augmente suite à un ajout de LIF après une culture de 24 ou 48 heures sans cette cytokine. Nous avons mis au point des tests fonctionnels permettant d’étudier la fonction des gènes cibles du LIF dans notre modèle d’étude. Ainsi, nous avons mis en évidence le rôle d’un gène « Pluri », Mras/Rras3, une petite GTPase de la famille Ras, dans la régulation de l’expression d’une part de marqueurs de pluripotence, tels que Oct4 et Nanog et d’autre part de marqueurs de différenciation, tels que Lef1 et Fgf5LIF (Leukemia Inhibitory factor), a cytokine Interleukin 6 family, allows maintaining the pluripotency of murine embryonic stem cells (mESC) in vitro. To understand the mechanisms of action of the LIF in this model, a microarray analysis was conducted and identified three « signatures LIF » : the « Pluri » (for Pluripotency) genes, whose the relative level of expression falls following the withdrawal of this cytokine, and two classes of « Lifind » (for LIF induced) genes, whose the relative expression level increases as a result of LIF addition after a culture of 24 or 48 hours without this cytokine. We have developed functional tests to study the function of the target genes of LIF in our study model. Thus, we have investigated the role of a « Pluri » gene, Mras/Rras3, a small GTPase of the Ras family, in the regulation of the expression on the one hand of markers of pluripotency, such as Oct4 and Nanog, and on the other hand of differentiation markers, such as Lef1 and Fgf5
5
Salloum, Georges. "Contribution à la commande robuste de la machine asynchrone à double alimentation." Phd thesis, Toulouse, INPT, 2007. http://oatao.univ-toulouse.fr/7534/1/salloum.pdf.
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Le travail présenté dans cette thèse apporte, entre autres, une contribution aux méthodes d'analyse et de synthèse de la commande robuste des Machines Asynchrones à Double Alimentation (MADA) alimentées par deux onduleurs de tension avec deux bus continus distincts. Nous introduisons, dans un premier chapitre, la commande vectorielle classique de la MADA munie de capteurs mécaniques. Ce chapitre se distingue par une nouvelle approche pour assurer le découplage des courants de la MADA dans un repère (d-q) conduisant à des fonctions de transfert simples, et par conséquent, un calcul simplifié des correcteurs. Ce chapitre se termine par une étude prouvant la robustesse du découplage et de la commande vis-à-vis des variations paramétriques de la machine. La commande robuste de la MADA, par l'approche H∞, est ensuite abordée en faisant une comparaison entre quatre stratégies de contrôle : la sensibilité mixte, une variante de la sensibilité mixte, le loop-shaping et la m-synthèse. Une étude par m-analyse de la robustesse en stabilité et en performance offre un critère de choix du correcteur. La réalisabilité du correcteur sera à son tour un critère déterminant du choix de la méthode de correction. Dans une dernière partie, nous centrons notre intérêt sur la commande robuste de la MADA sans capteurs mécaniques en travaillant sur des méthodes d'estimation de la vitesse et de l'angle mécanique. Nous limitons cette étude à l'introduction de deux méthodes d'estimation : La MRAS, éventuellement associée à un filtre de KALMAN, et l'injection d'une composante haute fréquence associée à un traitement numérique (FFT – STFT) pour en déduire la vitesse. La première approche est simple à implanter mais elle est très sensible aux variations paramétriques, surtout la résistance statorique, tandis que la deuxième est complètement insensible à ces variations mais très lourde en calcul. Dans cette partie, nous nous intéressons aussi à la commande numérique de la MADA.
6
Mališ, Martin. "Algoritmy bezsnímačového řízení pohonu se synchronním motorem." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220151.
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The goal of this thesis is to deal with comparison of algorithms in the field of sensorless control of permanent magnet synchronous motor. It is focused mainly on deterministic methods of estimation, verification of their dynamic responses and the influence of parasitic effects. Implementation of selected algortihms on DSP in fractional arithmetic with verification by Processor-in-the-loop method is described in second part. The last part describes use of algorithms on real drive.
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Pettersson, Ulf. "Identification and Adaptive Control of a Coordinate Measuring Machine." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2293.
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Important factors in manufacturing are quality and cost. Measuring machines play an important role for these fields. In order to meet higher demands on cost and accuracy, measuring machines can be constructed with weaker materials and increased mechanical flexibilities, and therefore there is a need to include the flexibilities in measuring machine models to obtain good performance.
The core theme in this thesis is modeling and idenfication of the physical parameters of drive mechanisms of a Brown&Sharpe Inc. Global A coordinate measuring machine. The approximation made is that the drive mechanisms can be described by a mass connected by springs, dampers and gear changes. It has been found that a one-spring model gives a reasonably good description of the studied CMM drive mechanism. The physical parameters of this model are identified using off-line algorithms. The algorithms are based on prediction error methods. For the off-line identification the MATLAB System Identification Toolbox and the bond graph representation is used.
The chosen model is then used for control. Traditional control and a Model-reference Adaptive System is derived and studied with the aim to increase the damping of CMM drive mechanisms. It is found that the adaptive system has very good disturbance rejection and can correct for drastic model errors. Another impact is that the damping of the studied drive mechanism can be increased with at least a factor of nine.
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Trinkūnaitė, Ingrida. "Asinchroninės bejutiklės pavaros modeliavimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110621_170245-16691.
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Baigiamajame darbe sudarytas uždarosios asinchroninės bejutiklės vektoriškai valdomos pavaros imitacinis modelis ir ištirtos charakteristikos. Teorinėje darbo dalyje yra aptariami asinchroninių elektros pavarų privalumai bei šiose pavarose naudojami greičio jutikliai. Aprašomi stebiklių privalumai bei trūkumai, pagrindžiamas jų naudojimas asinchroninėse pavarose. Nagrinėjami bejutiklių elektros pavarų ypatumai, aprašomi vektorinio valdymo bendrieji principai bei aprašomi bejutiklėse vektoriškai valdomose pavarose naudojamų stebiklių modeliai. Pateikiami du skirtingi asinchroninių variklių matematiniai modeliai. Tiriamojoje dalyje parenkamas asinchroninio variklio modelis, tiriant abiejų imitacinių modelių dinamines greičio charakteristikas. Sudaromas stebiklio imitacinis modelis. Tiriamos stebiklio greičio dinaminės charakteristikos, sudaroma uždaroji greičio reguliavimo sistema su stebikliu. Analizuojamos uždarosios greičio reguliavimo sistemos greičio charakteristikos be apkrovos, su šuoline apkrova ir harmoniškai kintančia apkrova. Nagrinėjama sistemos stiprinimo koeficiento įtaka uždarosios greičio reguliavimo sistemos greičio charakteristikų pereinamiesiams procesams. Magistro darbas baigiamas tyrimo išvadomis, kuriose aptariamas darbo rezultatų realaus pritaikymo galimybės. Darbą sudaro 8 dalys: įvadas, žymėjimai, literatūros šaltinių analizė, tyrimo tikslas ir uždaviniai, teorinė dalis, tiriamoji dalis išvados ir pasiūlymai, literatūros šaltiniai.The final master degree thesis presents sensorless vector controlled induction motor drive simulation model and characteristics. In the analytic part of master thesis advantages of induction motor drives and speed sensors are described. Advantages and disadvantages of speed estimators are presented and purpose of using them are proved. Peculiarities of sensorless motor drives, principles of vector control and models of speed estimators are analyzed. Two simulation models of induction motor are proposed. In the research part characteristics of induction motors are compared and motor model is chosen. Characteristics of open loop induction motor drive are investigated and simulation model of closed loop induction motor drive with speed estimator is designed. Characteristics of closed loop control system at no load, constant load and harmonic load are analyzed and influence of speed controller gain is considered. Thesis is closed with conclusions about designed system application in real projects. Structure: introduction, list of symbols, literature review, the study aims and objectives, the theoretical part, research part, conclusions and proposals, references.
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Mehazzem, Fateh. "Contribution à la commande d’un moteur asynchrone destiné à la traction électrique." Thesis, Paris Est, 2010. http://www.theses.fr/2010PEST1032/document.
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Le travail présenté dans cette thèse a pour objectif d'apporter une contribution aux méthodes de commande et d'observation des machines asynchrones destinées à la traction électrique. Dans ce contexte, plusieurs algorithmes ont été développés et implémentés. Après une présentation rapide de la commande vectorielle classique, de nouvelles approches de commande non linéaire sont proposées : il s'agit plus précisément de la commande backstepping classique et sa variante avec action intégrale. Une deuxième partie est consacrée à l'observation et à l'estimation des paramètres et des états de la machine, basée sur des structures MRAS-modes glissants d'une part et sur des structures de filtrage synchrone d'autre part. Une analyse détaillée du problème de fonctionnement à basse vitesse nous a conduit à proposer une solution originale dans le cadre d'une commande sans capteur mécanique. Le problème de la dégradation du couple en survitesse a été traité par un algorithme de défluxage basé sur la conception d'un contrôleur de tension. Enfin, nous avons proposé un algorithme d'optimisation afin de minimiser les pertes dans l'ensemble Onduleur-MachineThe work presented in this thesis aims to contribute to the control and observation of the induction machines for electric traction. Several algorithms have been developed and implemented. After a fast presentation of the classical vector control, new approaches of non-linear control are proposed : the classical backstepping and integral backstepping. A second part deals with the observation and the estimation of parameters and states of the machine, based on MRAS-Sliding Mode structures on one hand and on synchronous filtering structures on the other hand. A detailed analysis of the operation at low speed led us to propose an original solution for a Sensorless control. The torque degradation in field weakening zone was treated by a voltage regulation controller. Finally, we proposed losses minimization algorithm for the Inverter-Machine set
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Tanagardi, Mehmet. "Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7623.
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In recent years, multi-functional reconfigurable antennas (MRA) has attracted much attention in wireless communication. The reconfigurable antenna can adapt itself with changing system conditions, and it can provide different multi-functionalities which can give better system performances. Instead of using multiple antennas, a single reconfigurable antenna can provide the same performance and occupy less space. By using the parasitic layer technique, an antenna can be turned into a reconfigurable antenna. The main objective of this thesis is to study radiation pattern reconfiguration of the horn antenna by using the parasitic layer concept. The MRA consists of a single horn, dielectric loaded truncated pyramid (DLTP), and the parasitic layer. The antenna that is chosen in this thesis is the horn antenna because it provides high directivity. DLTP is used for magnification purpose. The results show that three modes of operations that provide better performances compared to the single horn antenna are achieved.
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Akin, Bilal. "State Estimation Techniques For Speed Sensorless Field Oriented Control Of Induction Motors." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1055953/index.pdf.
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This thesis presents different state estimation techniques for speed sensorlees
field oriented control of induction motors. The theoretical basis of each algorithm is
explained in detail and its performance is tested with simulations and experiments
individually.
First, a stochastical nonlinear state estimator, Extended Kalman Filter (EKF)
is presented. The motor model designed for EKF application involves rotor speed,
dq-axis rotor fluxes and dq-axis stator currents. Thus, using this observer the rotor
speed and rotor fluxes are estimated simultaneously. Different from the widely
accepted use of EKF, in which it is optimized for either steady-state or transient
operations, here using adjustable noise level process algorithm the optimization of
EKF has been done for both statesthe steady-state and the transient-state of operations. Additionally, the measurement noise immunity of EKF is also investigated. Second, Unscented Kalman Filter (UKF), which is an updated version of EKF, is proposed as a state estimator for speed sensorless field oriented control of induction motors. UKF state update computations, different from EKF, are derivative free and they do not involve costly calculation of Jacobian matrices. Moreover, variance of each state is not assumed Gaussian, therefore a more realistic approach is provided by UKF. In this work, the superiority of UKF is shown in the state estimation of induction motor. Third, Model Reference Adaptive System is studied as a state estimator. Two different methods, back emf scheme and reactive power scheme, are applied to MRAS algorithm to estimate rotor speed. Finally, a flux estimator and an open-loop speed estimator combination is employed to observe stator-rotor fluxes, rotor-flux angle and rotor speed. In flux estimator, voltage model is assisted by current model via a closed-loop to compensate voltage model&rsquo
s disadvantages.
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Agrebi, Zorgani Youssef. "Estimation adaptative de la vitesse et de la résistance rotorique pour la commande par orientation du flux statorique d’un moteur asynchrone sans capteur mécanique." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4360.
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Les travaux de recherche développés, dans ce rapport de thèse de Doctorat traitent la commande vectorielle indirecte par orientation du flux statorique d'une machine asynchrone avec ou sans capteur de vitesse. L'approche développée utilise la méthode adaptative avec modèle de référence. Le modèle de référence ainsi que le modèle ajustable, qui sont développés dans un repère lié au stator, sont utilisés pour l'estimation de la vitesse de rotation, de la résistance rotorique et enfin l'estimation mutuelle de la vitesse de rotation et de résistance rotorique d'une machine asynchrone à partir de la connaissance des courants et tensions statoriques. Pour annuler l'erreur statique lors de la régulation de la vitesse et améliorer par la suite les performances des résultats obtenus, le couple résistant, qui peut être considéré comme une perturbation, a été estimé en se basant sur les variables d'état du moteur à commander. Pour cela une procédure d'estimation du couple résistant de la même machine a été développée en se basant sur un observateur de type Luenberger. Les résultats de simulation numérique obtenus dans l'environnement Matlab- Simulink ainsi que les résultats expérimentaux, obtenus sur deux plates formes d'essais de machines asynchrones équipées chacune d'une carte de commande temps réel de type DS1104, valident bien les algorithmes développésThe research developed in this PhD report deal with indirect stator field oriented control (ISFOC) of an induction motor drive (IM), with and without speed sensor. The developed approach uses the method with Model Reference Adaptive System (MRAS). The reference model and the adjustable one, which are developed in stationary stator reference frame, are used to estimate the rotor speed, the rotor resistance and the simultaneous estimation of speed and rotor resistance of the (IM) from the knowledge of the stator currents and voltages. To cancel the static error in the speed control and ameliorate subsequently the performance results, the load torque, which can be considered as a disturbance, has been estimated based on the state variables of the motor to be controlled. For this, a procedure was developed to estimate the torque of the same machine based on a Luenberger observer. The numerical simulations results obtained with Matlab-Simulink software package as well as the experimental results, obtained on two platforms for testing asynchronous machines each equipped with a real time controller board of dSPACE, validate the developed algorithms
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Dušek, Martin. "Identifikace parametrů synchronních motorů s permanentními magnety." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218942.
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This work deals with the on-line identification of permanent magnet synchronous motor parameters. There is discussed the use of four different identification algorithms based on the least squares method and MRAS. The functionality of the algorithms is verified in Matlab - Simulink environment. Simulation results are compared in terms of rate and accuracy of identification, resistance to noise and other factors.
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Veselý, Libor. "Algoritmy bezsnímačového řízení synchronního motoru s permanentními magnety." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-233582.
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Algorithms of sensorless control of surface permanent magnet synchronous motors are discussed in the dissertation thesis. A method for position and speed estimation in high-speed region based on model reference adaptive system is described. Furthermore, classical approach using Kalman filtering was verified. Kalman filter expected the rotor speed to be constant as a modification of model using variable speed approach. These algorithms are not able to work at low speed region, thus a new method was proposed. This method is designed on extended Kalman filtering and uses the model which describes the stator inductance changes in - coordinates. At motor start, knowledge of initial rotor setup is required. The algorithm for initial rotor angle using high frequencies injected into the motor was proposed.
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Mehazzem, Fateh. "Contribution à la commande d'un moteur asynchrone destiné à la traction électrique." Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00597698.
Full textAbstract:
Le travail présenté dans cette thèse a pour objectif d'apporter une contribution aux méthodes de commande et d'observation des machines asynchrones destinées à la traction électrique. Dans ce contexte, plusieurs algorithmes ont été développés et implémentés. Après une présentation rapide de la commande vectorielle classique, de nouvelles approches de commande non linéaire sont proposées : il s'agit plus précisément de la commande backstepping classique et sa variante avec action intégrale. Une deuxième partie est consacrée à l'observation et à l'estimation des paramètres et des états de la machine, basée sur des structures MRAS-modes glissants d'une part et sur des structures de filtrage synchrone d'autre part. Une analyse détaillée du problème de fonctionnement à basse vitesse nous a conduit à proposer une solution originale dans le cadre d'une commande sans capteur mécanique. Le problème de la dégradation du couple en survitesse a été traité par un algorithme de défluxage basé sur la conception d'un contrôleur de tension. Enfin, nous avons proposé un algorithme d'optimisation afin de minimiser les pertes dans l'ensemble Onduleur-Machine
16
Pereira, William César de Andrade. "Controle de velocidade sensorless aplicado ao controle direto de torque da máquina de indução." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-14032014-082811/.
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Neste trabalho é apresentado um estudo sobre o controle de velocidade sensorless aplicado ao Motor de Indução Trifásico (MIT) visando sobretudo, melhorar o desempenho da máquina de indução em aplicações na região de baixa frequência de operação. Para tanto, propõe-se uma abordagem utilizando a técnica de controle Direct Torque Control (DTC) com Space Vector Modulation (SVM) em conjunto com o Observador de Fluxo com Modelo de Tensão e Corrente (OFMTC), o que possibilita a estimação precisa da posição do vetor de fluxo do estator em baixa velocidade. Para a estimativa da velocidade do rotor é utilizado a estratégia Model Reference Adaptive System (MRAS) com mecanismo de adaptação fuzzy, a fim de se diminuir a sensibilidade aos parâmetros da máquina. O desempenho da estratégia de controle de velocidade sensorless proposta é testada em simulações com diferentes condições de operação buscando reproduzir alguns dos problemas encontrados em aplicações práticas, utilizando o software Matlab. Os resultados obtidos foram condizentes com resultados encontrados na literatura, comprovando o bom desempenho do sistema de controle de velocidade proposto.This work deals with the sensorless speed control for Three-phase Induction Motor in order to improve its operation at low speed and low frequency. At first, a Direct Torque Control employing Space Vector Pulse with Modulation (SVPWM) based on Flux Observer (voltage and current model) is studied and evaluated due to its high accuracy of estimating the stator-flux at low speed. The Model Adaptive Reference (MRAS) with Fuzzy Controler is chosen in order to estimate the rotor speed. This choice is based on its capability of high performance during Three-phase Induction Motor operation even if the machines parameters and the load change during the operation. At last, some simulations with diferent operational conditions at low speed are carried out in order to test the sensorless control. The results show a good perfomance and agreed with the results shown in recent papers.
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Veselý, Ivo. "Identifikace parametrů synchronního motoru s permanentními magnety." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-263353.
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The purpose of this dissertation is to design identification methods for identifying a permanent magnet synchronous motor. The whole identification and motor control is carried out in d-q coordinates, and the program used for processing and control was the matlab simulink, together with the real time platform DSpace. The work focuses on two main areas of identification, off-line identification and on-line identification. For offline identification the frequency analysis was used with the lock rotor test to get three main parameters. They are the quadrature and direct inductances and stator resistance. In the online mode, the identified parameters were extended to magnet flux _f identified by MRAS method. The remaining parameters were again identified by frequency analysis, which was adapted into online mode, and simultaneously applied to the identification of several part in one time. The next method is Newton method, which is used for estimating stator resistance of the motor, without the need to apply any signal.
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Starck, Caroline, and Heidi Toivonen. "Patienter med MRSA - Upplevelser och erfarenheter av livet med MRSA." Thesis, Ersta Sköndal högskola, Institutionen för vårdvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:esh:diva-1421.
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Bakgrund: MRSA, metcillinresistenta staphyloococcus aureus, ökar idag i Sverige och i hela världen och bidrar till längre vårdtider, kostsamma behandlingar och mycket lidande för de drabbade patienterna och deras anhöriga. Syfte: Studien syftar till att undersöka hur patienter med MRSA upplever sin livssituation.Metod: Litteraturstudie baserad på tio kvalitativa vetenskapliga artiklar.Resultat: Resultatet presenteras i tre teman benämnda ”Att vårdas”, ”Upplevelse av social förändring” och ”Att vara smittad med MRSA” med tillhörande subteman. Patienterna beskriver att bristfällig eller utebliven information om MRSA, dess symtom och effekter var ett problem. De beskriver också rädsla för att smitta sina närstående och vänner. Många av de patienter som fått MRSA känner sig orena och smutsiga, som de fått spetälska eller pesten och de känner skam och skuld över att ha fått MRSA. Diskussion: Ett stort problem var diskrepansen i vårdpersonalens kunskaper om MRSA och deras handhavande av patienter som var smittade med MRSA. Många patienter blev oprofessionellt bemötta och fick felaktig och inadekvat information, vilket ledde till mycket oro och psykisk lidande. Att inte få information eller få felaktig information i vid sjukdom kan få stora konsekvenser för patientens livssituation.Background: MRSA metcillinresistenta staphyloococcus aureus is increasing both in Sweden and worldwide and contributes to longer time in the hospital, expensive treatments and suffering for the affected patients and their relatives. Aim: The aim of the study is to examine how patients with MRSA experience their life situation. Method: Literature study based on ten qualitative articles. Result: The results are presented in three themes, the "Caring", "Experience of Social Change" and "Being infected with MRSA" and related subthemes. Patients describe that inadequate or lack of information regarding MRSA, its symptoms and effects were a problem. They also describe the fear of infecting family and friends. Several of the patients with MRSA feel unclean and dirty, as they had leprosy or the plague, and they feel shame and guilt about being diagnosed with MRSA. Discussion: A major problem was the discrepancy in health professionals' knowledge of MRSA and their management of patients who were infected with MRSA. Several patients were treated unprofessionally and were given an inaccurate and inadequate information about their illness which contributed to anxiety and suffering. If patients do not receive information or receive incorrect information in the event of an illness, this can have major consequences for the patients´ life situation.
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Jakobsson, Aya, and Sofia Örjes. "Att vårdas med MRSA i sjukvården : En litteraturöversikt om MRSA-patienters vårdupplevelser." Thesis, Ersta Sköndal högskola, Institutionen för vårdvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:esh:diva-3665.
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Bakgrund: Meticillinresistenta Staphylococcus aureus (MRSA) är ett globalt bekymmer inom sjukvården. MRSA kan bland annat orsaka sårinfektioner, infektioner i skelett, lunginflammation, hjärninflammation, och kan leda till döden. I Sverige ökar MRSA med cirka 20 fall per vecka (en ökning med 33 % sedan år 2004). MRSA-smittspridning sker även utanför sjukhus, till exempel bland hushåll, dagis, skolan, äldreboende, samt via husdjur och livsmedelsproducerande djur. MRSA kan kolonisera människor utan symtom och det finns inte fullständigt fungerande eller effektiv behandling för att eliminera MRSA från kroppen. Patienter med MRSA bör vårdas i isoleringsvård för att undvika smittspridning och underlätta hygienarbetet. Detta kan leda till ökat lidande hos patienten genom isoleringsvård och längre behandlingstid. Syfte: Syftet var att beskriva patienters upplevelser av att vårdas med MRSA i sjukvården. Metod: En litteraturöversikt över nio vetenskapliga artiklar med kvalitativa metoder. Artiklarna lästes genom flera gånger och kategorier skapades från meningsinnehållet. Sedan sammanställdes innehållet med gemensamma nämnare från samtliga artiklar. Teman och subteman skapades utifrån det. Resultat: Resultatet visar att patienter som vårdas med MRSA upplever att smittan har stor påverkan på vårdupplevelsen, och resultatet kunde därför presenteras under följande fem teman med tre subteman: Information om MRSA och vården, Patientens kunskap och uppfattning om MRSA, Patientens känslor och upplevelser med subteman; Upplevelser över att vara MRSA-positiv, Känslor och upplevelser av isolering, Upplevelser av social påverkan av MRSA, Vårdkvalité och bemötande relaterat till MRSA, samt Tankar om framtiden. Diskussion: Resultatet diskuteras med en livsvärldsansats för att fördjupa förståelsen för patienternas upplevelse. Vårdpersonalen tycks i stor utsträckning kunna påverka patienternas upplevelse, negativt och positivt vid vård med MRSA. Patienternas kunskaper tycktes ha en avgörande roll för upplevelsen av vården.Background: Methicillinresistant Staphylococcus aureus (MRSA) is a global problem in health care. MRSA can cause wound infection, skeletal infection, pneumonia, and encephalitis and can result in death. In Sweden MRSA is increasing with about 20 cases per week (increasing by 33 % since year 2004). MRSA infectious spreading occurs even in the community, for example, among household, day-care, school, nursing home, through pets or farm livestock. MRSA can colonize without any symptoms. There is no completely effective treatment to get rid of MRSA. For prevention of infection spreading, MRSA patients have to be taken care by isolation, which can cause suffering through longer time at hospital and isolation. Aim: To describe patients' experiences of being cared for with MRSA in healthcare. Methods: A literature review based on 9 scientific articles with qualitative method. All articles were read several times and headlines were created based on context. Sentences with similar headlines were sorted out and categorized. Themes and subthemes were created. Results: The results show that patients treated with MRSA are experiencing that the disease has a major impact on their health care experience, and the results were therefore presented under five themes with three subthemes: Information about MRSA and care, The patients knowledge and understanding of MRSA, The patients’ feelings and experiences; with subthemes, The experiences of being a MRSA colonized patient, The experience of MRSA source isolation, The experience of social effects because of MRSA, Quality of care and personal treatment related to MRSA and Thoughts about the future. Discussions: The results are discussed with a life-world approach to deepen the understanding of patients' experience. Health professionals seem to affect patients' experiences, both negative and positive of being cared for with MRSA. Patients' knowledge seemed to have a crucial role in the experience of care.
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Amanbaeva, Asel, and Bernadetta Swierszcz. "Att vårdas för MRSA : En litteraturöversikt om patienters upplevelser av MRSA-vård." Thesis, Ersta Sköndal högskola, Institutionen för vårdvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:esh:diva-3923.
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Bakgrund: Meticillinresistenta Staphylococcus aureus (MRSA) ökar drastiskt inom sjukvården både i Sverige och i hela världen. Bakterien sprids vanligast från patient till patient via vårdpersonal då restriktioner om basala hygienrutiner inte följs. Att bli smittad med MRSA kan leda till svåra konsekvenser för patienter i form av infektioner i operationssår, i implanterade proteser, på hjärtklaffar, i lungorna och på hjärnhinnor. Patienter med MRSA vårdas i isolering för att förebygga att MRSA sprids vidare, vilket kan orsaka lidande hos patienter. Syfte: Denna uppsats syftar till att beskriva patienters upplevelser av MRSA-vård. Metod: Nio vetenskapliga kvalitativa artiklar ligger till grund för denna litteraturöversikt. Artiklarna har analyserats och sammanställts och nya teman uppkom efter de likheter som framkom i deras resultatdelar. Resultat: Resultatet visar att vårdandet förändrades efter MRSA-diagnos. Detta redovisas efter följande i sex teman och två subteman: Patienters kunskap om MRSA, Upplevelser av att bli smittad med MRSA, Patienters upplevelser av personalens kunskap och information, Upplevelser av personalens bemötande, Isolering med två subteman: Negativa upplevelser av isolering och Positiva upplevelser av isolering samt Oro för framtid. Diskussion: Resultatet diskuteras utifrån Katie Erikssons teori om den lidande människan som teoretisk utgångspunkt och utifrån patientens perspektiv. Vårdpersonalen kan påverka hur vårdandet upplevs. Brister i kunskap om MRSA hos vårdpersonalen, deras bemötande och följsamheten till hygienrutiner orsakar vårdlidande hos patienter med MRSA. Sjuksköterskans roll är att förebygga/lindra lidandet hos patienter.Background: Methicillin-resistant Staphylococcus aureus (MRSA) is increasing drastically in healthcare both in Sweden and worldwide. The bacteria is spread most commonly from patient to patient by health-care professionals when restrictions on basic hygiene is not followed. Becoming infected with MRSA can lead to severe consequences for the patients in terms of surgical site infection, the implanted prostheses, the heart valves, lungs, the meninges. Patients with MRSA are cared for in isolation to prevent MRSA from spreading further, which could cause distress in patients. Aim: This paper aims to describe patients' experiences of MRSA care. Methods: Nine scientific qualitative articles form the basis of this literature review. The articles were analyzed and compiled, and new themes emerged after the similarities that emerged from their performance parts. Results: The result shows that caring changed after MRSA diagnosis. This is recognized by the following six themes and two subthemes: Patients' knowledge about MRSA, Experiences of becoming infected with MRSA, Patients experiences of staff knowledge and information, experiences of treatment by staff, isolation with two subthemes: Negative experiences of isolation and positive experiences of isolation and Concerns for the future. Discussions: The results are discussed from the patient's perspective, with Katie Erikson's theory of the suffering person as a theoretical base. The nursing staff can affect how caring is experienced. Deficiencies in knowledge of MRSA in health care staff, their attitude and adherence to hygiene causes health suffering in patients with MRSA. The nurse's role is to prevent / alleviate the suffering of patients.
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Karlqvist, Eva, and Madeleine Kruse. "Intensivvårdspersonalens kamp mot MRSA." Thesis, Halmstad University, School of Social and Health Sciences (HOS), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-1701.
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Inom intensivvården (IVA) vårdas de mest allvarligt sjuka patienterna vilka ofta har svåra infektioner och ett nedsatt immunförsvar. Detta kan innebära en ökad risk att drabbas av meticillinresistenta stafylokock aureus (MRSA). Smittspridning av MRSA sker främst från sjukvårdspersonalens händer till patienterna. Syftet med litteraturstudien var att beskriva vilka åtgärder sjukvårdspersonalen inom IVA kan vidta för att minimera smittspridning av MRSA. Artiklarnas resultat visade att följsamheten var låg då det gällde att följa riktlinjer för noggrann handhygien. Orsaker till dålig följsamhet kan vara hög arbetsbelastning och bristande kunskap. Det fanns stora skillnader mellan de olika yrkeskategorierna då det gällde att följa riktlinjer för handhygien. Läkarna var de som följde riktlinjerna minst. Den viktigaste åtgärden för att minimera smittspridningen av MRSA är god handhygien och användning av handdesinfektionsmedel. Genom att utbilda sjukvårdspersonalen regelbundet samt ha lättillgängliga riktlinjer kan medvetenheten och kunskapen om MRSA öka. Detta medför troligtvis att personalen genomför adekvata åtgärder för att förhindra smittspridningen av MRSA. Då MRSA är ett ökande problem vore det angeläget att utföra observationsstudier beträffande hygienrutiner på olika intensivvårdsavdelningar i Sverige.
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Rocchi, Laura <1982>. "mRNAs translation and tumorigenesis." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4363/.
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Translational control has a direct impact on cancer development and progression. Quantitative and qualitative changes of cap-dependent translation initiation contribute to neoplastic transformation and progression. However, the idea that “alternative” mechanisms of translation initiation, such as IRES-dependent translation, can be involved in the tumorigenesis is emerging. Because the relevance of this kind of translation initiation in cancer progression is not so well clarified, the purpose of my work was to study the impact of IRES-dependent mRNA translation on tumourigenesis and cancer progression with particular regard for breast cancer. The data obtained clarify the function of cap-independent translation in cancer. Particularly they suggested that the deregulation of IRES-dependent translation can be considered a sort of pro-oncogenic stimulus characterized by the inhibition of the expression of some proteins that block cell growth and proliferation and by the over expression of other proteins that contributed to cell survival. In addition, under stress condition, such as a hypoxia, in immortalized epithelial cell lines, changes in cap-independent translation are associated with an induction of expression of stem cell markers, and with the selection of a sub group of cells that have an increased ability to self-renewing and therefore in the acquisition of a more aggressive phenotype.
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Kučera, Lukáš. "Rojová inteligence v MRDS." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219676.
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The background research in this Master’s thesis is focused on swarm intelligence. Further, there are two experiments described. They are based on released publications and they study behaviour of a group of robots during a puck gathering and during a target search. The actual thesis follows a repetition of these experiments in Microsoft Robotics Developer Studio (RDS), a free robotics simulation environment. The realization of both experiments in RDS is documented in detail and the achieved results are evaluated and compared with the results described in the publications. In conclusion, the thesis summarizes basic features, advantages and disadvantages of developing in RDS, based on a personal experience.
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Ersbrand, Mats, and Johan Jungman. "Säker omvårdnad vid MRSa." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26922.
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MRSA infektioner på uppåtstigande trend i Sverige och klassas som en allmänfarlig sjukdom. Syftet med litteraturstudien är att belysa de åtgärder som kan vara av betydelse beträffande adekvat handhygien för att minska spridning av MRSA infektioner. Arbetet är utfört som en litteraturstudie efter Goodmans sju steg i Willman et al (2006). Tio artiklar kvalitetsgranskades enligt en modifierad mall av Carlsson, S. & Eiman, M (2003). Alkoholens, handskarnas och informationens betydelse är det som beskrivs i denna studie som åtgärder för adekvat handhygien. Slutsatsen av resultatet är att upprepade informationstillfällen skulle vara den mest effektiva åtgärden för säker omvårdnad vid MRSA.MRSA infections of the rising trend in Sweden and is classified as a dangerous disease. The purpose of literature review is to illustrate the measures that may be relevant in respect of adequate hand hygiene to reduce the spread of MRSA infections. The work is done as a literature review of Goodmans seven steps in Willman et al (2006). Ten articles quality examined under a modified model of Carlsson, S. & Eiman, M (2003). Alcohol, gloves and information is described in this study as measures of adequate hand hygiene. The conclusion of the result is that repeated briefings would be the most effective measure for the safe care at MRSA.
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Grundkvist, Sara, and Nasima Zadran. "Att arbeta mot MRSA." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26149.
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De antibiotika resistenta bakterierna blir allt fler, Methicillin Resistenta Stafylokocker Aureus är en av dem. MRSA återfinns på väldigt många sjukhus världen över och är ett alltmer växande problem. Syftet med litteraturstudien är att belysa effekter av sjuksköterskans compliance avseende prevention och preventiva åtgärder vid risk för spridning av MRSA samt de riskmoment som uppstår vid omvårdnadsarbetet i generell sjukvård. Studien har utförts enligt sju steg för att ha ett systematiskt tillvägagångssätt. Sökningarna har gjorts i Pubmed och Cinahl, kvantitativa studier har inkluderats i litteratursökningen. Alla artiklar är kvalitetsgranskade med hjälp av granskningsprotokoll. Nio artiklar valdes till studien och utifrån dessa framkom resultat i fyra olika kategorier, barriärvård, compliance, handhygien samt riskmoment. Måttligt vetenskapligt bevis påvisar att fullgott smittskydd utgörs av både handskar och skyddsförkläden för att hindra kontaminering av arbetskläder. Studier visar även att compliance avseende prevention stärks genom utbildning. Därmed speglar samtliga resultat budskap om att patienten ska skyddas mot smitta precis som sjuksköterskan, då sjuksköterskan likväl kan utgöra en länk i smittkedjan.Antibiotically resistant bacteria are multiplying at an exponential rate in today's society and are threatening to consolidate into a serious problem in hospitals around the world. MRSA is part of this phenomena. This study intends to uncover and highlight the effectiveness of nurses' compliance to preventative efforts, to the precautions associated with activity where the risk of transmission of MRSA is a constant, and the hazardous circumstances arising out of the hospital and nursing environments. To ensure that the study maintained a thoroughly systematic procedure, it was conducted in seven separate steps. Pubmed and Cinahl have been utilised in the research, where quantitative studies have been included as part of the reviewed literature. The quality of the material has been ensured by applying a review protocol. Nine articles were selected to form the base of the study, which produced results in four categories respectively – barrier care, compliance, hand hygiene and hazardous circumstances. Moderate scientific evidence prompts the assertion that proper protection against transmission requires both protective gloves and aprons to shield work clothing from contamination. Studies have furthermore shown that compliance in the area of prevention is improved through training. All the results thus support the view that the patient ought to be protected to the same degree as the nurse, as the latter may inescapably constitute an extension of disease transmission.
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Ekström, Anna, and Emelie Karlsson. "Att vara MRSA- bärare." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-24743.
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Syfte: Att undersöka upplevelsen av att vara MRSA positiv. Metod: En litteraturöversikt efter anvisningar av Axelsson (2008). De nio artiklar som ingick kvalitetsgranskades efter en modifierad mall av Carlsson & Eiman (2003).Resultat: Av de granskade artiklarna framkom sex teman som redovisas: Kunskap/ uppfattning, Informationsbehov, Personalens kunskap, Rädsla för att föra smittan vidare, Information vid isoleringsvård och Psykisk påverkan vid isoleringsvård. Slutsats: Upplevelsen av att vara MRSA positiv varierar bland deltagarna i studierna. Det framkommer att kunskapen om MRSA är bristfällig. Flertalet studier pekar på att informationen som givits i samband med diagnos, behandling och isolering var bristfällig. Det är troligt att en bättre informerad patient kan bidra till att smittspridningen av MRSA minskar.Aim: To investigate the experience of being MSRA positive. Method: A literature review by directions of Axelsson (2008). The nine articles that are included were subjected to a modified model by Carlsson & Eiman (2003). Result: From the review of the articles six themes emerged: Knowledge/opinion, Information need, Staff knowledge, Fear of passing on the infection, Information at source isolation, The mental affects of source isolation. Conclusion: The experience of being MSRA positive varies among the participants in the studies. The studies also reveal a lack of knowledge. Most studies indicate that the information provided in connection with diagnosis, treatment and isolation was inadequate. It is likely that a better informed patient could reduce the spread of MRSA.
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Abrahamsson, Daria, and Sofi Miller. "MRSA – EN FÖLJETONG UTAN SLUT : Effekter av olika åtgärder i smittskyddsarbete mot MRSA." Thesis, Linnéuniversitetet, Institutionen för hälso- och vårdvetenskap, HV, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-9662.
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Bakgrund: Multiresistenta bakterier, däribland MRSA, är idag ett globalt samhällsproblem. Infektioner förorsakade av MRSA skapar ett onödigt lidande för patienter med utdragen vårdtid som i värsta fall kan resultera i ökad dödlighet. Enligt Smittskyddsinstitutet (2010) drabbades 1479 patienter förra året i Sverige. Med få verksamma antibiotika måste andra åtgärder tillämpas, så som basala hygienrutiner, screening, isoleringsvård och utökad städning av sjukhusmiljön. Det är dock viktigt att utvärdera åtgärdernas effekter för att kunna utföra smittskyddsarbete på bästa möjliga sätt. Syfte: Syftet var att undersöka effekterna av olika åtgärder i smittskyddsarbetet mot MRSA. Metod: Litteraturstudie med kvantitativ ansats baserad på tio vetenskapliga original artiklar. Analysen gjordes enligt Forsberg och Wengströms (2008) riktlinjer för meta-analys. Resultat: Studien visar att MRSA förekommer i kliniska miljöer samt förutom hos patienten även hos vårdpersonal. Förebyggande åtgärder som bland annat noggrann städning, basala hygienrutiner och screening hade varierande effekt och reducerade MRSA- förekomsten bäst i kombination. I vissa fall kunde brister i vårdpersonalens följsamhet (compliance) av hygienrutiner ses. Slutsats: För att reducera MRSA- förekomst och spridning är det viktigt att implementera de åtgärder som finns idag och som visat sig har effekt. För att genomföra detta krävs det att vårdpersonalens följsamhet blir bättre.
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Mccrea, Gavin. "Mrs Engels." Thesis, University of East Anglia, 2013. https://ueaeprints.uea.ac.uk/48694/.
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The creative component of the thesis consists of a novel entitled Mrs Engels. Mrs Engels is a first-person narrative from the perspective of Lizzie Burns, the Irish lover of the Communist leader Friedrich Engels. The action of the novel is focused on the years 1870-72 when Lizzie and Friedrich move from Manchester to London in order to be close to the Marx’s and the active international Communist scene there. The critical component consists of an essay entitled ‘Illusions of Truth’. ‘Illusions of Truth’ is a meditation on some of the questions raised when we speak of the category of ‘historical fiction’. It is a response to the fact that, often, discussions of historical fiction view ‘the past’ as textual and therefore to some degree unknowable, while taking for granted the knowability of ‘the present’. In other words, in order to assert the textuality of the past, many discussions of historical fiction juxtapose it to an immediately knowable present, sometimes called ‘direct’ or ‘present experience’. But is it true that the present is a more solid, knowable form of human experience than the past? Is direct engagement with reality even possible? Does the present exist at all, except as an historical fiction? The essay uses the theory of Michel Foucault, specifically his ‘archaeological’ and ‘genealogical’ approaches to history, as lenses through which to examine these questions. Grouping its analyses around the larger themes of time, space and truth, it considers whether anything in human experience can, in fact, be present and non-historical (and therefore entirely knowable and true). Can conscious human experience be anything other than historical and fictional? If indeed it cannot, is ‘historical fiction’ as a separate literary classification sustainable?
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Nevarko, Tatiana. "Translational control of neuronal mRNAs." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119601.
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The processes of learning and memory require accurate translational control of neuronal mRNAs. This control can be carried out through the regulation of the general translation machinery and upstream factors, as well as through the recognition and selective translation of specific mRNAs. In this work we explore two molecular mechanisms of translational control in neurons. First, we investigate the roles of RNA helicases eIF4A1 and DHX29 in controlling the translation of synaptically-localized mRNAs. We demonstrate the preferential translation of mRNAs with extensively structured 5'UTR, underlining the importance of this region in translational control. We also pinpoint the post-synaptic localization of DHX29 and propose a technique for monitoring the rate of 5'UTR-dependent translation in vivo with the use of a photoconvertible fluorescent reporter protein. Second, we study the role of cap-dependent translation in autism spectrum disorders (ASD) by examining translationally controlled mRNAs. We show that knockout of eIF4E binding protein 2 (4E-BP2, eIF4E repressor downstream of mTOR) or overexpression of eIF4E in mice lead to increased translation of neuroligin mRNAs, which can explain the autistic-like behaviours in these mice. Moreover, we design short hairpin RNAs packaged in lentiviral particles to modulate the expression of neuroligins in vivo. We use this technology to validate the mechanism of dysregulated neuroligin mRNA translation as the causal factor for the autism-like behaviour in the 4E-BP2 knockout mice. Finally, we propose a mechanism for the exaggerated translation of neuroligin mRNAs through their 5'UTRs. In conclusion, in this work we provide evidence that translational control of specific brain mRNAs is crucial for synaptic function and behaviour.Les processus d'apprentissage et de mémoire requièrent un contrôle précis de la traduction des ARNm présents dans les neurones. Ce contrôle peut être exercé au niveau de la machinerie traductionnelle et des facteurs en amont de celle-ci, mais aussi au niveau des ARNm, en reconnaissant et en traduisant les molécules messagères de façon sélective. Dans cet ouvrage nous étudions deux mécanismes de régulation traductionnelle dans les cellules nerveuses. En premier lieu, nous explorons les rôles des hélicases eIF4A1 et DHX29 dans la régulation de la traduction des ARNm localisés aux synapses. Nous confirmons que la traduction des ARNm contenant une région 5' non traduite (5'UTR) complexe est favorisée, soulignant de ce fait l'importance de cette région dans la régulation traductionnelle. Nous démontrons que DHX29 se trouve surtout dans l'élément postsynaptique et proposons une méthode de surveillance du taux de traduction in vivo selon la complexité de la 5'UTR à l'aide d'un gène rapporteur codant une protéine fluorescente photoconvertible. En second lieu, nous étudions le rôle de traduction dans le cas des troubles du spectre autistique (TSA) en examinant la régulation traductionnelle de certains ARNm. Nous démontrons que l'invalidation (knock-out) de 4E-BP2 (eIF4E-binding protein 2) ou la surexpression de eIF4E dans des souris mène à la traduction accrue des ARNm des neuroligines, ce qui pourrait expliquer le comportement autistique de ces souris. De plus, nous concevons des lentivirus remplis de petits ARN en épingle à cheveux (shRNA) destinés à moduler l'expression des neuroligines in vivo. Nous utilisons cette technologie afin de prouver que la dysrégulation de la traduction des ARNm des neuroligines est une cause majeure du comportement autistique parmi les souris knock-out pour 4E-BP2. Enfin, nous proposons une explication de la traduction exagérée des ARNm des neuroligines en examinant leur 5'UTR. Pour conclure, dans cet ouvrage nous fournissons la preuve de l'importance de la régulation traductionnelle des ARNm pour le propre fonctionnement du système nerveux.
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Gibbons, Cheryl Leanne. "Epidemiology of MRSA in Scotland." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20447.
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Staphylococcus aureus (S. aureus) is a bacterium that commonly colonises the skin and nares of around one third of otherwise healthy individuals. While colonisation is benign, S. aureus can cross skin and mucosal barriers to cause infections that manifest as clinical disease. Clinical outcomes are diverse and range from mild, non-complicated and often self-limiting skin and soft tissue infections (including boils, abscesses and cellulitis) to more severe and life-threatening conditions including pneumonia, toxic shock syndrome and bacteraemia. Medication isn’t always needed for mild S. aureus infections as often they resolve with time but, for severe or persistent cases, antimicrobial treatment is generally required. Following decades of widespread and intensive usage of topical, enteral and parenteral antimicrobials to treat S. aureus infections; AMR has become an established and ubiquitous problem in the treatment of infections caused by this microorganism, especially when in the methicillin resistant form (i.e. MRSA). The aim of this thesis was to examine aspects of S. aureus epidemiology (including MRSA and methicillin-sensitive S. aureus (MSSA)) in Scotland using statistical methods and data from several large public health databases. More specifically this involved: descriptions of spatial and temporal trends of morbidity and mortality; comparisons of epidemiological and molecular attributes (including antimicrobial resistance) of (1) MSSA and MRSA, and (2) the dominant clones of MRSA (i.e. EMRSA-15 and EMRSA-16); descriptions of spatial and temporal trends of antimicrobial prescribing in primary and secondary care and any associations between prescribing rates and MRSA antimicrobial resistance; and carrying out a hospital-level risk factor analysis of MRSA, testing hypotheses that hospital size, hospital connectivity (through shared transfer patients) and hospital category have an effect on hospital-level incidences of MRSA in mainland Scottish hospitals. Results showed that total S .aureus bacteraemia and MRSA bacteraemia in Scotland statistically declined over time (p < 0.0001), but MSSA bacteraemia did not (p > 0.05). While combined mortality rates (i.e. all MSSA deaths (both primary and secondary cause), or all MRSA deaths (both primary and secondary cause)) mirror these findings; case-fatality ratios (CFR) show no declines over time for either MRSA or MSSA. Results also show that several epidemiological factors point towards a predominant community source for MSSA isolates (i.e. outside healthcare) and hospital source for MRSA. Evidence for this included: (1) the lack of resistance genes in the MSSA population, (2) MRSA was more associated with long-term care and high-risk patients in the specialties care of the elderly, high dependency units/intensive care units (HDU/ICU), and surgery and conversely MSSA with specialties that commonly served outpatients, and (3) the abundance of non-EMRSA-15/non- EMRSA-16 ‘other’ clones in the MSSA population as compared with the hospital-associated CC22 (EMRSA-15) and CC30 (EMRSA-16) clones. EMRSA-15 was by far the most dominant MRSA clone in Scotland with EMRSA-16 declining significantly and non-EMRSA-15/non-EMRSA-16 clones causing an increasing number of infections (over the time period 2003-2013). EMRSA-16 was resistant to a larger number of antimicrobials than EMRSA-15, typically 9 versus 5, and while resistance varied for EMRSA-16 over the study period, resistance remained stable for EMRSA-15. There was little difference between clinical and screening MRSA isolates. Analyses of antimicrobial prescribing showed that prescribing rates of several drugs increased over time (2003-2013). Prescribing was far higher in primary care settings than in secondary care, although this differed between antimicrobials. Significant positive associations between prescribing and resistance rates were found for gentamicin (pr - p<0.0001, se - p<0.0001) and trimethoprim (pr - p<0.01, se - p<0.0001) in both primary (pr) and secondary (se) care, and clindamycin (p<0.0001) in primary care only. Finally, in Scotland there is a threshold of connectivity above which the majority of hospitals, regardless of size, are positive for MRSA. Higher levels of MRSA are associated with the large, highly connected teaching hospitals with high ratios of patients to domestic staff. While there were a number of data limitations, this body of work provides a better understanding of the epidemiology of S. aureus including MRSA in Scotland.
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Jeyaratnam, Dakshika. "The rapid detection of MRSA." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/the-rapid-detection-of-mrsa(762ea8c4-b8e9-4b77-9ac5-913bdb0e12bc).html.
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The control of meticillin-resistant Staphylococcus aureus (MRSA) is a global healthcare priority. Screening patients for MRSA carriage occupies a central position in this control. Conventional culture methods for MRSA screening take 2-3 days to produce a positive result. Polymerase chain reaction (PCR) based systems can detect MRSA within one day ('rapid screening') though these tests are more costly than culture tests. It is hypothesised that rapid detection of MRSA carriers will lead to faster implementation of control procedures, reducing the transmission of MRSA. The first study in this thesis validates a rapid method, IDI-MRSA ™ for use on pooled and non-nasal specimens. The second paper is a controlled trial of the IDI-MRSA™ test. It investigated whether rapid MRSA screening leads to a reduction in MRSA acquisition and was set on ten wards of a London teaching hospital. The main outcome was the MRSA acquisition rate (proportion of patients negative for MRSA who became MRSA positive). Secondary outcomes included test characteristics and measures of resource use. The intervention was PCR screening for MRSA compared with conventional culture. 6888 (82.3%) patients had full data. The overall MRSA carriage rate on admission was 6.7%. Rapid tests led to a reduction in median reporting time from admission (46 to 22 hours, P<0.001) and reduced the number of inappropriate pre-emptive isolation days between the two arms (399 v 277, P<0.001). 108 (3,2%) patients in the control arm and 99 (2.8%) in the intervention arm acquired MRSA. When confounding factors were taken into account the adjusted odds ration was 0.91 (95% confidence interval 0.61 to 1.234). Rates of MRSA transmission, wound infection, and bacteraemia were not statistically different between the two arms. On these data it is unlikely that the increased costs of rapid tests can be justified compared with alternative control measures against MRSA.
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Bock, Kerstin [Verfasser]. "MRSA an einem Krankenhaus der Maximalversorgung (2009) : eine retrospektive Auswertung von MRSA-Patientendaten zu Screening, Risikofaktoren und molekularbiologischen Untersuchungen der MRSA-Stämme / Kerstin Bock." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2014. http://d-nb.info/1062536355/34.
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Dierck, Melanie [Verfasser]. "Selektives MRSA-Screening bei Aufnahme auf Intensivstationen : Risikofaktoren für einen positiven MRSA-Status / Melanie Dierck." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2008. http://d-nb.info/1022941933/34.
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Brum, Raphael Martins. "Conception hybride CMOS et mémoires magnétiques : applications aux architectures programmables." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20141.
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Avec la réduction continue des dimensions des transistors CMOS, le développement des mémoires statiques du type SRAM énergétiquement efficientes et de hautes densités devient de plus en plus difficile. Les dernières années ont vu l'apparition de nouvelles technologies de mémoire, qui ont attiré l'intérêt de la communauté académique, ainsi que de nombreux acteurs industriels. Parmi ces technologies, la STT-MRAM se distingue pour ses caractéristiques très avantageuses, comme sa faible consommation, ses performances et sa facilité d'intégration dans une technologie de fabrication CMOS. En plus, les MRAMs sont des technologies non-volatiles, avec une endurance élevée, nous allons utiliser cette caractéristique pour proposer de nouvelles fonctionnalités aux systèmes intégrés, notamment sur les architectures de processeur et les dispositifs reconfigurables.Une comparaison entre plusieurs amplificateurs de lecture, utilisables pour concevoir des matrices de mémoire et des cellules séquentielles a été aussi menée. Afin de démontrer la faisabilité de la conception hybride CMOS/MRAM plusieurs prototypes ont été conçus sur une technologie 28nm CMOS FDSOI et une technologie magnétique capable de produire des MTJ perpendiculaires STT de 200nm. Nous avons appliqué ces briques de base au monde du processeur notamment en proposant un processeur capable de conserver un état sain lors d'une erreur d'exécution. Les résultats obtenus confirment que le surcout de ces techniques est tout à fait compatible avec la démarche de conception d'un circuit intégré actuelWith the downscaling of the CMOS technology, it is becoming increasingly difficult to design power-efficient and dense static random-access memories (SRAM). In the last two decades, alternative memory technologies have been actively researched both by academia and industry. Among them, STT-MRAM is one of the most promising, having near-zero static power consumption, competitive performance with respect to SRAM and easy integration with CMOS fabrication processes. Furthermore, MRAM is a non-volatile memory technology, providing for new features and capabilities when embedded in reconfigurable devices or processors. In this thesis, applications of MRAM to embedded processors and field-programmable gate-arrays (FPGAs) were investigated. A comparison of several self-referenced read circuits, with application for both memory arrays and sequential cells is provided, based on MTJ compact models provided by our project partners. To demonstrate the feasibility of the proposed circuits, we laid-out and fabricated independent, self-contained sequential cells and a hybrid, multi-context CMOS/MTJ memory array, using state-of-the-art 28nm FDSOI CMOS technology, combined with a 200nm perpendicular STT-MTJ process. Finally, we used these building blocks to implement instant on/off and backward-error recovery capabilities in an embedded processor. Results obtained by simulation allowed us to verify that these features have minimal impact on performance. An initial layout implementation allowed us to estimate the impact on silicon footprint, which could be further reduced by improvements in the MTJ integration process
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Braman, Jade A. "Prevalence of Methicillin-Resistant Staphylococcus aureus (MRSA) on Human and Equine Contact Surfaces in a Large Veterinary Teaching Hospital." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1305748270.
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Lemmer, Beate [Verfasser]. "Einsatz einer Single-locus-MRSA-PCR zum Aufnahmescreening auf Methicillin-resistente Staphylococcus aureus (MRSA) / Beate Lemmer." Ulm : Universität Ulm. Medizinische Fakultät, 2012. http://d-nb.info/1024534170/34.
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SOARES, Cynthia Regina Pedrosa. "Prevalência da Colonização Nasal por Staphylococcus aureus Resistente à Meticialina em Pacientes Ambulatorias Vivendo com HIV/aids de Hospital Terciário no Estado de PERNAMBUCO-BRASIL." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/17525.
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CAPEs
Staphylococcus aureus é um dos microrganismos mais comuns em infecções patogênicas no mundo, tornando-se de grande importância hospitalar e comunitária. Pessoas vivendo com HIV/aids (PVHA) são mais susceptíveis de serem colonizados por Staphylococcus aureus resistente á meticilina (MRSA). S. aureus pode adquirir resistência a antimicrobianos, devido à presença de genes de vários tipos contidos no cassete cromossômico estafilocócico - mec (SCCmec) conferindo resistência a diversos antibióticos. A investigação da colonização por MRSA foi realizada através do isolamento de amostras oriundas de secreção nasal e posteriormente screening de oxacilina combinado a reação de PCR convencional para investigação do gene mecA. Foram entrevistados no estudo 500 PVHA ambulatoriais do hospital terciário. Aproximadamente 95% fazia uso de terapia antirretroviral, sendo que 89,3% destes apresentavam contagem de células CD4 >200 e 73,4% com carga viral ≤100 cópias. A maioria foi do sexo masculino (64,4%), com média etária de 41,5 anos e se declararam de cor parda (54,7%). Exposição a antimicrobianos nos últimos 12 meses foi encontrado em 27,4% dos indivíduos e 25,1% relataram uso de drogas ilícitas ao menos uma vez na vida. Colonização nasal por S. aureus foi encontrada em 31,4% (157/500) da totalidade dos indivíduos estudados, nos quais, 14% (22/157) foram MRSA. A colonização foi maior nos indivíduos acima de 40 anos, entre os que relataram uso de drogas ilícitas ao menos uma vez na vida, nos que não havia registro de exposição prévia a antimicrobianos nos últimos 12 meses, porém, não foi encontrada nenhuma associação de MRSA com as variáveis estudadas. A colonização de MRSA, embora alta, não foi associado com as variáveis estudadas para fator de risco em PVHA. O perfil antimicrobiano mostra alta resistência aos antibióticos mais utilizados para profilaxia e tratamento por infecções bacterianas. Esse estudo pode contribuir para orientar na vigilância e conduta terapêutica entre as PVHA.
Staphylococcus aureus is one of the most common pathogenic microorganisms in infections in the world, making it of great importance hospital and community. People living with HIV/aids (PVHA) are more likely to be colonized with Staphylococcus aureus resistant to methicillin (MRSA). S. aureus may acquire resistance to antibiotics due to the presence of various types of genes contained in the chromosomal staphylococcal cassette - mec (SCCmec) conferring resistance to various antibiotics. The investigation of MRSA colonization was carried out by isolating samples from nasal discharge and subsequently screening oxacillin combined with conventional PCR to investigate the mecA gene. They were interviewed in the study 500 outpatient PVHA tertiary hospital. Approximately 95% made use of antiretroviral therapy, and 89.3% of them had CD4 cell counts> 200 and 73.4% with viral load ≤100 copies. Most were male (64.4%) with a mean age of 41.5 years and declared mulatto (54.7%). antimicrobial exposure in the last 12 months was found in 27.4% of patients and 25.1% reported using illicit drugs at least once in life. nasal colonization by S. aureus was found in 31.4% (157/500) of all subjects studied, in which, 14% (22/157) were MRSA. The colonization was higher in individuals over 40 years among those who reported using illicit drugs at least once in life, in which there was no antimicrobial previous exposure record in the last 12 months, however, it found no MRSA association with the variables studied. Colonization of MRSA, although high, was not associated with the variables for risk factor for PVHA. The antimicrobial profile shows high resistance to antibiotics most commonly used for treatment and prevention of bacterial infections. This study may help guide surveillance and therapeutic management among PVHA.
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Aune, Paulin, and Lene-Marie Eidaker. "MRSA smittade patienters erfarenheter av isoleringsvård." Thesis, Mittuniversitetet, Avdelningen för omvårdnad, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-21866.
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Seabra, de Azevedo João Batista. "Test et fiabilité des mémoires MRAM." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20155/document.
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De nos jours, les mémoires occupent une grande superficie en silicium dans les System-on-Chip. Très largement utilisés, les mémoires Flash non volatiles présentent encore plusieurs inconvénients. Les MRAMs permettent de répondre à toutes les problématiques liées aux Flash. Cependant, elles sont sujettes à des défauts comme tout autre type de mémoire. Très peu de travaux portent sur le test de MRAM et la recherche effectuée dans ce domaine vise principalement la première génération de mémoires magnétiques. Dans ce travail, la physique derrière la modélisation MTJ est abordée. Cette compréhension est le point de départ pour développer un modèle fiable. Le MTJ est l'élément de base pour les technologies MRAM. L'injection de défauts résistif ouvert, résistif courts-circuits et capacitives ont été réalisées dans le but d'analyser les mécanismes de défaillance spécifiques de la TAS-MRAM. Un test du type march spécifique est proposé à l'aide des résultats d'analyses d'injection de défauts et de l'association de chaque mécanisme de défaillance à un modèle de défaut fonctionnel spécifique. L'évolution du TAS-MRAM est la MRAM à base MLU qui est également développée par Crocus Technology. Finalement, un modèle MLU-MTJ sera élaboré et discutéMemories occupy most of the silicon area in nowadays System-on-Chips. Though widely used, non-volatile Flash memories still have several drawbacks. MRAMs have the potential to mitigate almost all Flash related issues. However, they are prone to defects as any other kind of memory. Only few studies on MRAM testing can be found in the literature, and target mainly the first generation of Magnetic Memories.In this work the physics behind MTJ modeling is discussed in this work as this understanding is the starting point in order to develop a reliable model. MTJ is the basic building block of MRAMs. Moreover, Resistive-open, resistive-bridge and capacitive of defect injection are performedin order to analyze specific failure mechanisms of TAS-MRAMs. As result of defect injection analyses and the association of each failure mechanism to a specific functional fault model, a specific march test is proposed. The evolution of TAS-MRAMs is the MLU based MRAM also developed by Crocus Technology. Finally, a MLU-MTJ model will be developed and discussed
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Das, Jayita. "Auxiliary Roles in STT-MRAM Memory." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5613.
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Computer memories now play a key role in our everyday life given the increase in the number of connected smart devices and wearables. Recently post-CMOS memory technologies are gaining significant research attention along with the regular ones. Spin Transfer Torque Magnetoresistive RAM (STT-MRAM) is one such post-CMOS memory technology with a rapidly growing commercial interest and potential across diverse application platforms. Research has shown the ability of STT-MRAM to replace different levels of memory hierarchy as well. In brief, STT-MRAM possesses all the favorable properties of a universal memory technology. In this dissertation we have explored the roles of this emerging memory technology beyond traditional storage. The purpose is to enhance the overall performance of the application platform that STT-MRAM is a part of. The roles that we explored are computation and security. We have discussed how the intrinsic properties of STT-MRAM can be used for computation and authentication. The two properties that we are interested in are the dipolar coupling between the magnetic memory cells and the variations in the geometries of the memory cell. Our contributions here are a 22nm CMOS integrated STT-MRAM based logic-in-memory architecture and a geometric variation based STT-MRAM signature generation. In addition we have explored the device physics and the dynamics of STT-MRAM cells to propose a STT based clocking mechanism that is friendlier with the logic-in-memory setup. By investigating the logic layouts and propagation style in the architecture, we have also proposed different techniques that can improve the logic density and performance of the architecture.
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Anthony, Donald D. "Translation initiation: Typical and atypical mRNAs." Case Western Reserve University School of Graduate Studies / OhioLINK, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=case1055862170.
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Sarno, Thomas. "Caractérisation sécuritaire des mémoires magnétiques MRAM." Thesis, Saint-Etienne, EMSE, 2015. http://www.theses.fr/2015EMSE0796.
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La MRAM est une technologie de mémoire non-volatile émergente, elle a la particularité de stocker les données sous forme d’orientations de moments magnétiques. Ses performances sont intéressantes et surpassent les technologies actuelles sur plusieurs aspects. Crocus Technology développe une nouvelle génération de MRAM, les TAS-MRAM (pour ThermallyAssistedSwitching MRAM). Ces MRAM ont la particularité d’effectuer les opérations d’écritures à hautes températures, améliorant ainsi la consommation électrique et facilitant sa réduction d’échelle. Les TAS-MRAM sont développées pour des applications sécuritaires ou critiques, cependant la technologie MRAM utilise des principes physiques liés aux interactions magnétiques qui sont relativement peu étudiés en termes de sécurité du composant.L’objet du travail de cette thèse est d’évaluer les potentielles faiblesses de sécurité pour cette technologie. En particulier la capacité des MRAM à garantir l’intégrité et la confidentialité des informations qui sont stockées a été étudiée. Ce travail est divisé en deux parties, une première partie est consacrée à l’analyse de la résistance des MRAM aux attaques physiques avec un focus tout particulier sur l’étude des effets des champs magnétiques sur l’écriture, la lecture et la rétention des données ainsi que les différentes solutions envisagées pour réduire ces effets. Une étude des effets de la température a également été réalisée. L’autre partie du travail porte sur l’étude des émissions électromagnétiques et l’analyse de plusieurs méthodes pour retrouver le poids de Hamming des données manipulées par la mémoire et de ce fait en extraire de potentiels secrets ou données sensiblesMRAM (magnetoresistive RAM) is an emergent non-volatile memory technology; it has the particularity to store data in magnetic moments orientations. It has very interesting characteristics that overwhelm mature technologies on several points. Crocus Technology is developing a new MRAM technology called TAS-MRAM (for Thermally Assisted Switching). During write operations, this new MRAM technology uses a current to heat the memory cell. This reduces the power consumption and makes scalability easier. TAS-MRAM are developed for secure or critical applications but this technology relies on spintronic, a field of physics not much studied for electronics security.This work aims to evaluate potential security weaknesses of this technology. More specifically the memory capacity to guarantee data confidentiality was studied. This work was divided in two parts; one part is dedicated to the analysis of MRAM resistance against physical perturbations, with a special focus on magnetic fields (both static and pulsed) effects on read and write operations as well as their effects on data retention. Various methods to reduce these effects were tested and compared. The effect of high temperature was also studied.The second part focuses on the analysis of electromagnetic emissions of the MRAM components during its operations. Methods to retrieve the Hamming weight of data written in the memory are exposed and compared
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Werner, Malin, and Nathalie Gatsara. "Den levda erfarenheten som MRSA-bärare : en systematisk litteraturstudie." Thesis, Linnéuniversitetet, Institutionen för hälso- och vårdvetenskap, HV, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-23778.
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Brix, Gabriele. "Methicillin-resistenter Staphylococcus aureus (MRSA) am Universitätsklinikum Ulm - eine retrospektive Analyse für den Zeitraum 2002 - 2006." [S.l. : s.n.], 2009. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-66603.
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Nilsson, Grimstad Kristoffer. "Evaluation of the Oxford Nanopore Minion for the identification and differentiation of MRSA and non-MRSA isolates." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18528.
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Staphylococcus aureus are bacterial pathogens causing infectious diseases. Methicillin-resistant S. aureus, or MRSA, carry the mecA or mecC genes generating resistance to β-lactam antibiotics. MRSA is problematic to treat and crucial to rapidly detect while current diagnostic workflows are time-consuming. DNA sequencing offers an alternative to existing methods. Illumina, the leading sequencing platform, is time-consuming and generates short reads. The Oxford Nanopore Technologies MinION presents rapid sequencing protocols, generating long reads at reduced accuracy. Here, the MinION device was evaluated to rapidly identify and differentiate between MRSA and non-MRSA isolates, with estimations on turn-around-times for clinical implementation.DNA extracted from 12 bacterial isolates were sequenced on the MinION. The automated workflow for raw MinION reads EPI2ME called taxonomy and resistance genes. MinION reads and corresponding Illumina reads were also assembled with Unicycler with short-read, long-read and hybrid assembly, and analyzed with the Center for Genomic Epidemiology bioinformatic tools. MinION and Illumina reads analyzed with the 1928 Diagnostics S. aureus pipelines were also compared. All tools correctly identified mecA in confirmed MRSA isolates, and mecC in an unconfirmed isolate. Similar results in terms of species, virulence and resistance genes were observed. Strain typing was problematic for MinION reads compared to Illumina, due to increased error rates. The minimum estimated turn-around-time for the MinION in this project, from library preparation, was approximately 6.5 hours to 7.5 hours per sample. Although further investigations are required, the MinION offers an intriguing alternative to current methods for identifying MRSA, aiding in rapid diagnosis and treatment.
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Billington, Josie. "Mrs Gaskell : England's Tolstoy?" Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309949.
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Löfgren, Hanne-Maj, and Veronica Olsson. "Pestsmittad : upplevelser av att vara MRSA- bärare." Thesis, Kristianstad University College, School of Health and Society, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-6254.
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Bakgrund: Meticillin resistenta staphylococcus aureus (MRSA) är ett växande problem i Sverige, bakterien som tidigare spreds i sjukhusmiljö sprids numera även ute i samhället. Syfte: Syftet med litteraturstudien var att belysa hur det är att leva och vårdas med MRSA. Metod: Arbetet genomfördes som en allmän litteraturstudie. Resultat: Bärarna upplevde kontakten med vården olika, vissa var nöjda med informationen de fick medan andra var missnöjda. Isoleringsvården som tillämpades, upplevdes av bärarna både som positivt samt negativt. I vardagslivet såg bärarna begränsningar, de isolerade sig socialt för att skydda andra, vissa bärare fortsatte leva sina liv som de gjort förut. En del av bärarna berättade att det kändes som att vara pestsmittad. Diskussion: Kunskapen och informationen från vårdpersonalen bör förbättras för att kunna tillgodose bärarnas behov både angående bakterien samt sociala åtgärder då de smittats. De bör även arbeta så att de hygieniska föreskrifterna efterföljs, för att undvika att agera smittspridare och orsaka onödigt lidande hos bärarna. Isoleringsförhållandena bör förändras till en mer skälig tid för bärarna, då det är vanligt förekommande att de under denna tid utvecklar en depression.
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Müller, Christina [Verfasser]. "Posttranskriptionale Regulation von Myelin-mRNAs / Christina Müller." Mainz : Universitätsbibliothek Mainz, 2015. http://d-nb.info/1080277358/34.
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Routh, Joshua. "Determining variable contagiousness of MRSA by setting." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/281793.
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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.Objective and Hypothesis Methicillin resistant Staphylococcus aureus (MRSA) is currently a major cause of skin and soft tissue infections (SSTI) in the United States. In order to characterize the spread of MRSA in the pediatric population we built a probabilistic, discrete-event, individual-based simulation. Specifically, our model looked at the spread of MRSA in households and at schools to determine if there was a difference in communicability between the two settings. Methods We developed a probabilistic, discrete-event, individual-based model. This model was validated using insurance billing data for skin and soft tissue infections. The first validation trained the model for two years of data, and validated it with the next two years of data. The second method trained the model in one region and validated it in another. Following the validation, the Poisson-bootstrap resampling method was used to find specific values for a contagiousness factor(CF) in households and schools. Results Both methods of validation supported the model with no statistically significant difference. The bootstrap resulted in a CFhousehold of 30.69 (95% CI [29.09, 32.29]) and a CFschool of 0.55 (95% CI [0.46 to 0.64]). Effective reproduction number for the school setting was found to be 0.0015 and 0.06 to 3.04 for households of different size. Conclusion In this study we characterize a marked difference in communicability in the household and at school, which has not previously been shown. The identification of colonization clusters in households can be used to design strategies reduce the disease burden. The model can be used to simulate and predict responses to different interventions.
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Ebrey, Richard John. "MRSA in biofilms and the healthcare environment." Thesis, University of Exeter, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531680.
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