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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Die englischen Kronzeugen : 1130-1330 /

Röhrkasten, Jens. January 1900 (has links)
Texte remanié de: Diss.--Friedrich-Meinecke-Institut--Freie Universität Berlin, 1987.
2

Desenvolvimento de protocolos de neuronavegação para estudos de estimulação magnética transcraniana e suas aplicações em voluntários controle e pacientes com acidente vascular cerebral / Development of protocols for Transcranial Magnetic Stimulation Neuronavigated studies and Its Applications in Control and Patients with Stroke subjects

Peres, André Salles Cunha 05 October 2012 (has links)
Objetivos A estimulação magnética transcraniana (TMS, do inglês: Transcranial Magnetic Stimulation) e as imagens funcionais por ressonância magnética (fMRI, do inglês: functinal Magnetic Resonance Imaging) são duas técnicas não invasivas de investigação de atividade do sistema nervoso central. Porém essas duas técnicas utilizam estratégias diferentes para mensurar a atividade cerebral, sendo que a TMS avalia a resposta elétrica enquanto que a fMRI a resposta hemodinâmica. Nosso intuito nesse trabalho foi criar ferramentas para a comparação dessas duas técnicas no mapeamento do córtex motor, bem como utilizando as ferramentas desenvolvidas, fazer uma comparação dos mapas motores de pacientes com AVC com sujeitos assintomáticos, e nesses dois grupos, também realizar uma avaliação nos efeitos no córtex motor da eletroestimulação sensorial (SES, do inglês: Sensory Electric Stimulation) pelas técnicas de TMS e fMRI. Métodos Paro o mapeamento vetorial do campo magnético produzido pela bobina de TMS utilizamos fantomas que simulavam o tecido cerebral e realizamos medidas de imagens de ressonância magnética (MRI, do inglês: Magnetic Resonance Imaging) de fase em três direções para a construção do mapa vetorial. Uma vez dominada a técnica de mapeamento por imagens de fase, a utilizamos para auxiliar na construção de bobinas para estimulação periférica e pequenos animais. Para realização do mapeamento do córtex motor com TMS desenvolvemos um sistema de neuronavegação (Neuronavegador InVesalius) e um programa para análise dos sinais de eletromiografia (MEPHunter), bem como um segundo programa para fazer o corregistro dos mapas de produzidos pela TMS com os mapas de fMRI (TMSProjection). Em posse dessas ferramentas, pudemos realizar o mapeamento do córtex motor de pacientes com AVCi crônicos. Para tanto estimulamos uma área quadrada de 25cm2 do escalpo sobre o córtex motor e coletamos o potencial evocado nos músculos abdutor curto do polegar ipsi e contralateral à TMS, e nos músculos flexor e extensor radial do carpo, contralaterais à TMS. Para a realização das fMRIs realizamos um paradigma evento-relacionada com um protocolo de abrir e fechar a mão. Por fim avaliamos os efeitos da SES à 3Hz com um única sessão de 30 minutos, realizando medidas de potencial evocado e fMRI imediatamente antes e imediatamente após à SES. Resultados O sistema de neuronavegação juntamente com o conjunto de programas computacionais possibilitou a realização dos estudos clínicos. Nossos dados mostraram uma correlação maior entre os mapas de MEP e os mapas de fMRI nos sujeitos normais do que nos pacientes com AVC, principalmente no hemisfério afetado. Nossos resultados também sugerem que a SES pode provocar modulação na excitabilidade cortical, causando redução da excitabilidade cortical das regiões motoras, quando aplicados na frequência e duração utilizadas nesse estudo. Conclusão O mapeamento de campo magnético por MRI é uma boa alternativa para medir campos complexos e pode ser utilizado no desenvolvimento de novas bobinas de estimulação magética. O neuronavegador Invesalius, o MEPHunter e o TMSProjection são ferramentas poderosas para estudos em neuroimagens podendo ser ampliado seu uso para outras áreas como neurologia e fisioterapia. Quanto aos estudos clínicos acreditamos que o fator que mais colabora para a pior correlação dos mapas dos pacientes é a redução de fibras corticoespinhais e a plasticidade, e que a SES aplicada a 3Hz em uma única sessão tem um efeito agudo de redução da excitabilidade do córtex motor. / Background and Purpose - Transcranial magnetic stimulation (TMS) and functional magnetic resonance images (fMRI) are two noninvasive techniques to investigate the central nervous system activity. These two techniques use different strategies to measure brain activity, once the TMS evaluates the electrical response while the fMRI studies hemodynamic response. Our purpose in this study was to create tools for the comparison of these two techniques for mapping the motor cortex. Latter, using these tools, we compared the motor maps of stroke patients and healthy subjects. Furthermore, we evaluated the effects of electrical stimulation in the sensory motor cortex (SES) by TMS and fMRI techniques. Methods - In order to map the magnetic field vector produced by the TMS coil, we used phantoms that simulated brain tissue and performed measurements of magnetic resonance phase images in three directions, in this way, composing the vector map. Then, we used this technique for helping to build small coils for peripheral and small animals stimulation. For the TMS mapping, we developed a neuronavigation system (InVesalius neuronavigator) and a program to analyze the electromyogram responses (MEPHunter). Secondly, a program to co-register the TMS and fMRI maps (TMSProjection) was created. Using these tools, we mapped the motor cortex of the chronic ischemic stroke patients. For this, we stimulated a square scalp area of 25cm2 over the motor cortex and collected the motor evoked potential (MEP) in the abductor pollicis brevis, ipsilateral and contralateral to TMS, and the flexor and extensor carpi radialis, contralateral to TMS. FMRI was also acquired using an event-related paradigm where the volunteers were asked to open and close their hand. Finally, we evaluated the effects of 3Hz SES in a single 30-minute session, performing measurements of TMS and fMRI before and immediately after the SES. Results - The neuronavigation system and the developed softwares made possible clinical studies. We also found a higher correlation between the MEP and fMRI maps in normal subjects than in stroke patients, especially in the affected hemisphere. Additionally, Our results suggested that SES may cause reduction in cortical excitability of motor regions, when applied with the frequency and duration used in this study. Conclusion - The magnetic field MRI mapping is an efficient alternative for complex fields measuring and can be utilized in the development of new TMS coils geometry. The neuronavigator InVesalius, MEPHunter and TMSProjection are powerful tools for neuroimaging studies and other areas as neurology and physiotherapy. We believe that the most important factor that contributes to the correlation decrease between the MEP and fMRI maps of the patients is the reduction of functional corticospinal fibers and the plasticity of motor areas. In this sense, the 3 Hz SES showed to be a potential technique as therapy in spastic patients.
3

ADHD Läkemedel : Påverkar föräldrars utbildningsnivå medicinering av barn med ADHD? / Do parents educational level impact on medicate ADHD children?

Svensén, Sofia January 2014 (has links)
Studiens syfte var dels att undersöka om det fanns skillnader iförskrivning av centralstimulantia hos barn som kunde kopplas tillföräldrarnas utbildningsnivå och dels att undersöka om det fannsskillnader i förskrivning av centralstimulantia vid nydiagnosticeradADHD som kunde kopplas till föräldrarnas utbildningsnivå. Uppgifterom studiepopulationen hämtades som aggregerad data frånläkemedelsregistret, patientregistret och utbildningsregistret.Deltagarantal för första forskningsfrågan var 37959 personer, varav25385 pojkar och 12574 flickor. Den andra forskningsfråganomfattade 9443 personer varav 5931 pojkar och 3512 flickor.Åldrarna på deltagarna var 5-24 år. Resultaten från analyser av denförsta forskningsfrågan visade att barn vars föräldrar hadegymnasium som högsta utbildning var den grupp som hade störstandel behandlade. I den andra forskningsfrågan sågs inga skillnadermellan föräldrarnas utbildningsnivåer och andelen behandlade vidnydiagnosticerad ADHD. / This study examined some factors that can influence which childrenthat medicate with Central Nervous System (CNS) drug. Are there alink between differences in CNS drug use for children with ADHDconnected to parents’ educational level. The research questions of thisstudy were: 1) What are the impacts of parents’ education level onCNS drug use by children with ADHD? and 2) Are there differencesbetween these group of children and children newly diagnosed withADHD in this regard? Aggregated data for this study was collectedfrom The national patient register, Pharmaceutical register, andEducation register. Number of participants in the first group was37959 and the second group consisted of 9443 children. The resultsshowed that children whose parents had Swedish gymnasium as theirhighest education were the ones with the highest treatment proportion,but there were no differences in time of treatment considering theparental education level.
4

Desenvolvimento de protocolos de neuronavegação para estudos de estimulação magnética transcraniana e suas aplicações em voluntários controle e pacientes com acidente vascular cerebral / Development of protocols for Transcranial Magnetic Stimulation Neuronavigated studies and Its Applications in Control and Patients with Stroke subjects

André Salles Cunha Peres 05 October 2012 (has links)
Objetivos A estimulação magnética transcraniana (TMS, do inglês: Transcranial Magnetic Stimulation) e as imagens funcionais por ressonância magnética (fMRI, do inglês: functinal Magnetic Resonance Imaging) são duas técnicas não invasivas de investigação de atividade do sistema nervoso central. Porém essas duas técnicas utilizam estratégias diferentes para mensurar a atividade cerebral, sendo que a TMS avalia a resposta elétrica enquanto que a fMRI a resposta hemodinâmica. Nosso intuito nesse trabalho foi criar ferramentas para a comparação dessas duas técnicas no mapeamento do córtex motor, bem como utilizando as ferramentas desenvolvidas, fazer uma comparação dos mapas motores de pacientes com AVC com sujeitos assintomáticos, e nesses dois grupos, também realizar uma avaliação nos efeitos no córtex motor da eletroestimulação sensorial (SES, do inglês: Sensory Electric Stimulation) pelas técnicas de TMS e fMRI. Métodos Paro o mapeamento vetorial do campo magnético produzido pela bobina de TMS utilizamos fantomas que simulavam o tecido cerebral e realizamos medidas de imagens de ressonância magnética (MRI, do inglês: Magnetic Resonance Imaging) de fase em três direções para a construção do mapa vetorial. Uma vez dominada a técnica de mapeamento por imagens de fase, a utilizamos para auxiliar na construção de bobinas para estimulação periférica e pequenos animais. Para realização do mapeamento do córtex motor com TMS desenvolvemos um sistema de neuronavegação (Neuronavegador InVesalius) e um programa para análise dos sinais de eletromiografia (MEPHunter), bem como um segundo programa para fazer o corregistro dos mapas de produzidos pela TMS com os mapas de fMRI (TMSProjection). Em posse dessas ferramentas, pudemos realizar o mapeamento do córtex motor de pacientes com AVCi crônicos. Para tanto estimulamos uma área quadrada de 25cm2 do escalpo sobre o córtex motor e coletamos o potencial evocado nos músculos abdutor curto do polegar ipsi e contralateral à TMS, e nos músculos flexor e extensor radial do carpo, contralaterais à TMS. Para a realização das fMRIs realizamos um paradigma evento-relacionada com um protocolo de abrir e fechar a mão. Por fim avaliamos os efeitos da SES à 3Hz com um única sessão de 30 minutos, realizando medidas de potencial evocado e fMRI imediatamente antes e imediatamente após à SES. Resultados O sistema de neuronavegação juntamente com o conjunto de programas computacionais possibilitou a realização dos estudos clínicos. Nossos dados mostraram uma correlação maior entre os mapas de MEP e os mapas de fMRI nos sujeitos normais do que nos pacientes com AVC, principalmente no hemisfério afetado. Nossos resultados também sugerem que a SES pode provocar modulação na excitabilidade cortical, causando redução da excitabilidade cortical das regiões motoras, quando aplicados na frequência e duração utilizadas nesse estudo. Conclusão O mapeamento de campo magnético por MRI é uma boa alternativa para medir campos complexos e pode ser utilizado no desenvolvimento de novas bobinas de estimulação magética. O neuronavegador Invesalius, o MEPHunter e o TMSProjection são ferramentas poderosas para estudos em neuroimagens podendo ser ampliado seu uso para outras áreas como neurologia e fisioterapia. Quanto aos estudos clínicos acreditamos que o fator que mais colabora para a pior correlação dos mapas dos pacientes é a redução de fibras corticoespinhais e a plasticidade, e que a SES aplicada a 3Hz em uma única sessão tem um efeito agudo de redução da excitabilidade do córtex motor. / Background and Purpose - Transcranial magnetic stimulation (TMS) and functional magnetic resonance images (fMRI) are two noninvasive techniques to investigate the central nervous system activity. These two techniques use different strategies to measure brain activity, once the TMS evaluates the electrical response while the fMRI studies hemodynamic response. Our purpose in this study was to create tools for the comparison of these two techniques for mapping the motor cortex. Latter, using these tools, we compared the motor maps of stroke patients and healthy subjects. Furthermore, we evaluated the effects of electrical stimulation in the sensory motor cortex (SES) by TMS and fMRI techniques. Methods - In order to map the magnetic field vector produced by the TMS coil, we used phantoms that simulated brain tissue and performed measurements of magnetic resonance phase images in three directions, in this way, composing the vector map. Then, we used this technique for helping to build small coils for peripheral and small animals stimulation. For the TMS mapping, we developed a neuronavigation system (InVesalius neuronavigator) and a program to analyze the electromyogram responses (MEPHunter). Secondly, a program to co-register the TMS and fMRI maps (TMSProjection) was created. Using these tools, we mapped the motor cortex of the chronic ischemic stroke patients. For this, we stimulated a square scalp area of 25cm2 over the motor cortex and collected the motor evoked potential (MEP) in the abductor pollicis brevis, ipsilateral and contralateral to TMS, and the flexor and extensor carpi radialis, contralateral to TMS. FMRI was also acquired using an event-related paradigm where the volunteers were asked to open and close their hand. Finally, we evaluated the effects of 3Hz SES in a single 30-minute session, performing measurements of TMS and fMRI before and immediately after the SES. Results - The neuronavigation system and the developed softwares made possible clinical studies. We also found a higher correlation between the MEP and fMRI maps in normal subjects than in stroke patients, especially in the affected hemisphere. Additionally, Our results suggested that SES may cause reduction in cortical excitability of motor regions, when applied with the frequency and duration used in this study. Conclusion - The magnetic field MRI mapping is an efficient alternative for complex fields measuring and can be utilized in the development of new TMS coils geometry. The neuronavigator InVesalius, MEPHunter and TMSProjection are powerful tools for neuroimaging studies and other areas as neurology and physiotherapy. We believe that the most important factor that contributes to the correlation decrease between the MEP and fMRI maps of the patients is the reduction of functional corticospinal fibers and the plasticity of motor areas. In this sense, the 3 Hz SES showed to be a potential technique as therapy in spastic patients.
5

DEVS Unified Process For Integrated Development and Testing of Service Oriented Architectures

Mittal, Saurabh January 2007 (has links)
Service Oriented Architectures (SOA) present challenges to current model-based software engineering methodologies such as Rational Unified Process (RUP). In this research effort we propose a process called DEVS Unified Process (DUNIP) that uses the DEVS formalism as a basis for automated generation of models from various requirement specifications and realization as SOA collaborative services. DEVS is inherently based on object oriented methodology and systems theory, and categorically separates the Model, the Simulator and the Experimental frame, and has been used for systems Modeling & Simulation over the years. DUNIP integrates these concepts into DEVSbased Bifurcated Model-Continuity life-cycle development methodology. The life-cycle begins by specifying the system requirements in a number of different formats such as state-based, BPMN/BPEL-based, message-based requirement specifications. DUNIP then automates the generation of DEVS models capable for distributed collaboration. The collaboration uses an XML-based DEVS Modeling Language (DEVSML) framework that provides the capability to integrate models that may be expressed in different DEVS implementation languages. The models are also made available for remote and distributed real-time execution over the SOA middleware in a manner transparent to the user. A prototype simulation framework has been implemented and is illustrated with an application to a system of collaborating military systems implemented and tested using Bifurcated Model-Continuity methodology. We also show how the Department of Defense Architecture Framework (DoDAF) can be enhanced to incorporate simulation based executable models using the DUNIP process.
6

Livvstil,stress och hälsa hos skolelever från olika socioekonomiska förhållanden

Palmer, Maria January 2006 (has links)
<p>Forskning tyder på att stress kan påverka barns hälsa och att senare tids ökning av barns ohälsa är relaterat till socioekonomisk status (SES). Studiens syfte var att studera sambanden mellan SES, stress och hälsa hos barn. Totalt 102 barn från åk 4 i två skolor med låg respektive hög SES deltog i enkätundersökningen. Resultaten visar marginella skillnader i stress och hälsa mellan de båda SES-grupperna; dock var magvärk och huvudvärk signifikant vanligare hos barnen i låg-SES-gruppen. Vidare fanns mindre könsskillnader avseende livsstilsfrågor, dock ej direkt i relation till stress och hälsa. Sammantaget visar studien inte på några stora skillnader i relation till SES vilket kan bero på skillnader i gruppstorlek mellan låg respektive hög SES gruppen.</p>
7

Ungdomars hälsa, livskvalitet, socioekonomiska status och upplevelse av kontroll i vardagen

Backman, Marlena January 2010 (has links)
Syftet med den här studien var att undersöka den hälsorelaterade livskvaliteten hos elever på högstadiet samt hur denna förhåller sig till elevernas socioekonomiska status och upplevelse av kontroll. 154 elever från fyra olika kommunala skolor i Sverige besvarade ett formulär gällande deras hälsa, livskvalitet och känsla av kontroll. Eleverna delades in i olika grupper, hög/låg-SES, beroende på medelinkomsten i deras kommun. Resultatet visar på en signifikant skillnad i elevernas HRQoL. Högre grad av kontroll visades vara förknippat med bättre hälsa. Ingen skillnad i HRQoL beroende på eleverna SES upptäcktes. Inte heller några signifikanta interaktionseffekter mellan de två variablerna kontroll och SES.
8

Application Analysis on Ventilation Operation Strategy of Fixed Guideway System

Chuang, Yung-chun 06 July 2010 (has links)
Underground fixed guideway system has become an important solution to alleviate over-crowded population problems , especially in urban areas. During the planning stage, the station and the underground tunnel formed an enclosure which necessitated environmental control in order to facilitate thermal comfort and safety in case of fire. In this study, SES program has been utilized as a tool in evaluating the performance of the tunnel ventilation system under normal, congestion , and emergency operation modes, using an actual railway underground project as an example. Conclusions has been drawn that safety criteria can be met successfully, following the SES simulation results with recommendations made to facilitate successful ventilation modes.
9

Ontology/Data Engineering Based Distributed Simulation Over Service Oriented Architecture For Network Behavior Analysis

Kim, Taekyu January 2008 (has links)
As network uses increase rapidly and high quality-of-service (QoS) is required, efficient network managing methods become important. Many previous studies and commercial tools of network management systems such as tcpdump, Ethereal, and other applications have weaknesses: limited size of files, command line execution, and large memory and huge computational power requirement. Researchers struggle to find fast and effective analyzing methods to save maintenance budgets and recover from systematic problems caused by the rapid increment of network traffic or intrusions. The main objective of this study is to propose an approach to deal with a large amount of network behaviors being quickly and efficiently analyzed. We study an ontology/data engineering methodology based network analysis system. We design a behavior, which represents network traffic activity and network packet information such as IP addresses, protocols, and packet length, based on the System Entity Structure (SES) methodology. A significant characteristic of SES, a hierarchical tree structure, enables systems to access network packet information quickly and efficiently. Also, presenting an automated system design is the secondary purpose of this study. Our approach shows adaptive awareness of pragmatic frames (contexts) and makes a network traffic analysis system with high throughput and a fast response time that is ready to respond to user applications. We build models and run simulations to evaluate specific purposes, i.e., analyzing network protocols use, evaluating network throughput, and examining intrusion detection algorithms, based on Discrete Event System Specification (DEVS) formalism. To study speed up, we apply a web-based distributed simulation methodology. DEVS/Service Oriented Architecture (DEVS/SOA) facilitates deploying workloads into multi-servers and consequently increasing overall system performance. In addition to the scalability limitations, both tcpdump and Ethereal have a security issue. As well as basic network traffic information, captured files by these tools contain secure information: user identification numbers and passwords. Therefore, captured files should not allow to be leaked out. However, network analyses need to be performed outside target networks in some cases. The distributed simulation--allocating distributing models inside networks and assigning analyzing models outside networks--also allows analysis of network behaviors out of networks while keeping important information secured.
10

Livvstil,stress och hälsa hos skolelever från olika socioekonomiska förhållanden

Palmer, Maria January 2006 (has links)
Forskning tyder på att stress kan påverka barns hälsa och att senare tids ökning av barns ohälsa är relaterat till socioekonomisk status (SES). Studiens syfte var att studera sambanden mellan SES, stress och hälsa hos barn. Totalt 102 barn från åk 4 i två skolor med låg respektive hög SES deltog i enkätundersökningen. Resultaten visar marginella skillnader i stress och hälsa mellan de båda SES-grupperna; dock var magvärk och huvudvärk signifikant vanligare hos barnen i låg-SES-gruppen. Vidare fanns mindre könsskillnader avseende livsstilsfrågor, dock ej direkt i relation till stress och hälsa. Sammantaget visar studien inte på några stora skillnader i relation till SES vilket kan bero på skillnader i gruppstorlek mellan låg respektive hög SES gruppen.

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